Fiancee may be bi... suggestions

[Confusedfiancee]

Hi guys,
I am new to the group and I am in need of some advice about my fiancee and how to handle her requests. I am a straight male and my fiancee has said she is bi-curious, but I really have no clue if she is or not. We have been together for 3 years and and during our few months together we told each other many things about our sexual past... i.e. that I had a mmf (no male touching) and a mff threesome with a friend of mine. She constantly brought up a threesome with me after this, but always saying she didn't want to do it. I was fine with that, but told her that if she wanted to do either a mmf threesome or a mff threesome I would be fine with it. After we got serious, the threesome talk died down, though she would bring up another woman sometimes in the passion of sex. I would reiterate that I am happy with her, and do not need another woman. I did tell her that I have had fantasies about watching her with another woman, but I wanted to keep them at that... fantasy. What leads me to believe she maybe bi, she that she does watch porn, but it is entirely centered on women masturbating and showing their vagina. Watching this type of porn is the only way she can have a clitoral orgasm. I have given her gspot orgasms, but no matter how hard I try she can't have a clitoral orgasm unless I am gone and she is watching solo female or lesbian porn.
She toyed around with the idea and would ask me from time to time, but my reply was always the same. Finally after one conversation, I told her it would be alright, but the 2 ground rules I had was that I had to be present, and it could only be a one time thing, to which she agreed. She looked for a bit and didn't really do anything about it, so I assumed it was over. We got engaged, and then she stated she was happy with me and did not need anyone else.
Recently though she decided she wanted to try again, she has joined an online dating site with a bi-sexual status with the intentions of meeting female friends and a possible lover. However, this time she did not tell me about her profile this time and talked to a few women. I discovered it the other night when she opened up an email at dinner and needless to say I was a bit annoyed. First she lied about it being old and she forgot to delete it, then she lied about not talking to anyone. We had originally agreed that the talk of her being with another woman was over and that she should not be doing this. After talking, I told her that I would be fine with it if she agreed to my original ground rules: that I be present, and that it be a one time thing. She then got upset and complained that she wanted a best friend (we just moved to a new city, and she doesn't know many people), she could only sleep with someone she knew, and that afterwards she couldn't just abandon someone she slept with (she has only had one one-night stand and did not care for it again). She finally got mad at me and stated that she was going to delete the profile. She still hasn't deleted the site.
Does anyone have advice? I don't want to suppress her if she is bisexual, but at the same time I am not comfortable with her having another long term relationship with another woman. I believe it would kill our relationship. help!

[tenni]

You may benefit by knowing a few things about bisexuals
.
a/ fluid aspect to bisexuality. Many bisexuals report that their attraction to one gender or the other other can vary. It can be fluid. It may range from no interest in the same sex play and the amount of time this lasts can vary from person to person and even with the same person through their lifetime.


b/ It is looking more and more that she is bisexual. Her bisexuality is not going to go away. It is something that will be in your relationship. You are going to have to deal with this. She is not going to be happy repressing it and you seem to be aware of this.


c/ woman on woman sex while male partner watches.
That can be a difficult situation to get to happen. Some bisexual women are not as interested in having a male watch them with a woman as there are guys wanting to watch girl on girl action. You may want to rethink your boudary rules. What is the reason why you want to be in the room with her when she is with a woman? Jealousy? sexual arousal for yourself? or ?


d/ Bisexuals may need same sex play but that doesn’t mean that they are in love with the same gender person. This sexual physical need without emotion is more common in biguys but it may apply to her as well. It is more like a friendship with sex..yep could be friend with benefit concept. It is true though that some bisexuals may love two people one of each gender.


e/ boundary rules should be acceptable to both you and her otherwise you end up with cheating if the urge is strong for same sex play. Point c may be at the root why she is going behind your back. There may be other reasons. She may just not be comfortable with you in a room when she is making love to another woman.


At any point, there seems to be a need for a more honest discussion between you.

I'm sure that some bisexual women will post with other information for you. Best of everything to both of you.

[biblkman]

I agree with what tenni said, but I would also like to add that it sounds like she is bi and really wants to explore but she is being limited on what and when she can do, witch is understandable you two are engaged and this is a big thing, but like tenni said it seems like your being too demanding on what her actions will be, seems like she was excited about it but whenever it comes up she withdraws or lies.

If you really want to be understanding and supportive make it about her.

I understand its about compromise but the " rules " has got to go that sounds too controlling.

Her bisexuality most likely isn't going away and if you don't be more open to what it is she wants than she may just do it without you knowledge.

I understand its sometimes hard for the partner of a bisexual so I wish u luck

[Confusedfiancee]

I'm not controlling her, but I have let it be known that if she wants to explore, I would just perfer there to be guidelines to keep our relationship from falling apart. Regardless I have asked that she be honest with me throughout the whole process, but it doesn't seem that way. I have asked to be included and present, so that she doesn't feel she has the right to do it whenever she wants. I have explained that she were to do this without my consent, then I would consider it cheating. .. if the shoe were on the other foot, would it be considered cheating if I had sex with another woman? Her answer would be yes. Her having sex with another man would be considered cheating. So what makes a woman any different? The compromise is that if she wanted to step out, then I should be involved somehow or I should be allowed to also step out. She is extremely jealous, so me being with another woman or involved in a threesome is out ot the question, therefore I should be allowed to watch. I really don't see how this is controlling. If I were controlling I would say no and let thqt be it. I am willing to compromise by even agreeing to let her be with another woman. I just want it to be fair and understand my concerns. And yes I do admit watching is for my pleasure.

The other thing is about a friend with benefits type of person for her, again I want her to see this from my perspective. .. would she want me hanging around women I have slept with in the past? Her answer would be a definite no. I would prefer for it to be with someone random, so there is not a greater chance of not cheating.

[kaylacolline]

hey there, I also agree with what Tenni said. amazing advice. its also great to hear your side of the story too confused. I am a bi female and have a straight bf. we've been together for 5 years now and had pretty much the same conversations you and you fiancé have had. Although, I did know that I was bi before going into the relationship as did he. We struggled for a while because it was like I was stuffing the lady loving side of me back in the closet. I was constantly staring at women and craving them. we even had sex a bit less because of it. We ended up having a couple of threesomes, which don't get me wrong was VERY fun but I wasn't able to get as intimate with a girl as I wanted. I didn't want to focus on another dick in the room. I cant explain it but two women together is so different. I needed my girl time even if its not as often as I like. Thus, my bf and I are in a somewhat open relationship. I realize that it seems a bit extreme. But imagine being confused most of your life about feelings you have for something that seems so wrong and then wanting to explore it and being told no...just my two cents. hope all goes well :)

[tenni]

“if the shoe were on the other foot, would it be considered cheating if I had sex with another woman?”


This is a common attitude from monosexuals(hetero or gay). It is only cheating when you break the rules. The problem is with coming to terms with the rules for both of you. Read again what Kayla wrote about the pull that bisexuals can experience as to what sex they are involved with. She is not like you. We are not like monosexuals. We are different. Cross gender relationships are not like a bisexual's need for both genders.


Do not think of it as much as giving permission. You do not own her but you have the right to do what you want as far as staying in the relationship. You can really only give yourself permission to accept her bisexuality or not.


She may have to open up her resistance to the open relationship rules and accept you being sexually with a woman if that is what you really want for the relationship is to continue. I don’t feel very positive that you have it in your perspective to make being in a relationship with a bisexual work. If you take some time and try to learn about her thoughts that differ from your own, you may be able to evolve your perspective.

Another thought is to realize that love involves wanting your partner to be happy. This may include your partner being intimate with another woman to make her happy. If being happy for you means being with another woman, then she may have to accept that. She is not asking to be sexually with another man is she? Same gender play is not equal to opposite gender sex play though.

[dickhand]

It doesn't have to be if both of you can be flexible and understanding .

[Gearbox]

Just coz she is bisexual, doesn't mean that she doesn't need to work on her jealousy issues. If you are expected to deal with her having a FWB, then she must do the same for you no matter what the gender IMO.
You have knowingly got engaged to a bi just as she has knowingly got engaged to a hetro. Being hetro shouldn't disqualify you from having equal rights & rules in the relationship.

Before you do anything, the jealousy should be confronted and discussed in honest detail. It's that which puts relationships at risk.

[Lover_Not_Fighter]

Hi

I'm a noob here but Your situation rang a bell with me, I would have to ditto Mr. Gearbox's advice. If she want's to explore sex outside your relationship either bi or not it's a two way road!!! If she's not willing to discuss it then I would suggest that your relationship might be on the outs. If your relationship is going to survive then she must deal with her jealousy problem.

I do wish you luck either way!!

[jimdawg]

“if the shoe were on the other foot, would it be considered cheating if I had sex with another woman?”


This is a common attitude from monosexuals(hetero or gay). It is only cheating when you break the rules. The problem is with coming to terms with the rules for both of you. Read again what Kayla wrote about the pull that bisexuals can experience as to what sex they are involved with. She is not like you. We are not like monosexuals. We are different. Cross gender relationships are not like a bisexual's need for both genders.


Do not think of it as much as giving permission. You do not own her but you have the right to do what you want as far as staying in the relationship. You can really only give yourself permission to accept her bisexuality or not.


She may have to open up her resistance to the open relationship rules and accept you being sexually with a woman if that is what you really want for the relationship is to continue. I don’t feel very positive that you have it in your perspective to make being in a relationship with a bisexual work. If you take some time and try to learn about her thoughts that differ from your own, you may be able to evolve your perspective.

Another thought is to realize that love involves wanting your partner to be happy. This may include your partner being intimate with another woman to make her happy. If being happy for you means being with another woman, then she may have to accept that. She is not asking to be sexually with another man is she? Same gender play is not equal to opposite gender sex play though.

I'll disagree with you on one main point, Tenni: It is a change in status and it may not be for everyone. He is allowed to think about his own happiness too! And I think it could be very taxing on someone to commit to something that is only on a technicality to "accept"-I don't see why it is OK for someone to have many lovers because they happen to be bi and not straight.

You can be bisexual and still monogamous. The question, thus, gets down to monogamy and what type, and I'll agree which rules should apply. Different peoples have different sets, and you don't have to say "monosexual" to get there-I disagree that bisexuals somehow have inherently different needs than "monosexuals!" You can also be monosexual and not monogamous.

And expectations do change in a relationship; I think it is needed to secure consent when such a change is made; for instance, I had a girlfriend who was disinterested in sleeping with me once she started sleeping with women. I fully encouraged her to get with women, but not to completely neglect me! So of course, we broke up. I didn't compare it to "What would she think if I slept with a woman" the way a straight guy might, and I already knew she would've disapproved (hypocritically) if I slept with another guy as she had a fear bi men were somehow gay. Which was I guess founded in denial, that she was the gay one and didn't want to admit that. Either way, I broke it off, as the change in status to hot and heavy to dead fish was rather sudden, I felt ignored, and didn't appreciate it. I wasn't jealous or anything, but even if I were, that's not necessarily the problem. In all situations, this wasn't the right woman for me.

The question this guy needs to ask himself is...she can be bi, but can he be comfortable with a woman who needs to share experiences with women? This is very taxing on most people and I think it is VERY selfish to expect the answer here to be yes. Especially if he isn't free to have his own pursuits at comfort. Some people can handle it, of course. But, to be honest, I wouldn't go for it. I'd rather monogamy or openness-not openness for one person (this is, of course, a personal choice) due to the excuse of bisexuality and unsatisfied needs. Honestly, if the OP loves his girl enough and thinks it'll all be fine, then it doesn't matter much and he'd have to choose either his love of her or discomfort of who she is.

I say this knowing I want a girl who would be OK with me having the occasional guy, so I will quickly point out my apparent hypocrisy; but I also believe that would be unreasonably taxing on most (not all) women and subsequently I wouldn't be able to do that and have a relationship with most women, unless something about them made me foresake caring. Which has happened before. Usually I find it easiest to just find a woman with the same sexual preferences as me-hence why I exclusively date bisexuals with a hint of openness.

[tenni]

I'll disagree with you on one main point, Tenni: It is a change in status and it may not be for everyone. He is allowed to think about his own happiness too! And I think it could be very taxing on someone to commit to something that is only on a technicality to "accept"-I don't see why it is OK for someone to have many lovers because they happen to be bi and not straight.”


Is it really a change of status? She said that she watches lesbian porn and masturbates. She stated that she didn’t want a threesome but he did. He is not a monogamist. It is merely coming to consensus as to the boundary rules. If you are bisexual, you should pay attention to the fluid aspect of bisexuality. Whether you call it a change of status or ebb and flow of sexual attraction, she has admitted to it. She has not changed her status as she said that she was completely happy with him and now is interested with same sex activity. Bisexual all the way even if she has not labelled herself.

Of course, he is allowed to think of his happiness. If he is not happy with a bisexual with an ebb and flow sexual attraction to both sexes, then end the engagement.

Why is it not ok for a bisexual to have one lover of each sex? It seems most logical to me. Effectively wants two lovers himself but is upset with the OP's fiancé?

[jimdawg]

You state clearly that monosexuals think that a bisexual sleeping around gives them license to do the same, albeit with permission.

I'm adamant that there is no difference and gender shouldn't be an issue.

Truthfully, if I'm with someone who has another "best friend" and wants to "play around" then I feel it is in my rights to do the same, regardless of gender. I have an instinct to spread my seed far and wide, as much of an instinct he or she has to be with people who aren't me, if not further. My orientation has nothing to do with that. If she wants an FWB, he should have one, and I don't think it'd make a difference for most women if the guy slept with a girl or guy-the women who would tolerate me fooling around with a guy at all tolerated me fooling around with women. Those that thought it was gross thought it was just as abhorrent. And that includes bi women who I've been with-you'd be shocked how many bi women reject me on the grounds that I'm bi.

I fundamentally believe that bisexuals are NOT different like stated. The main differences are who bisexuals are attracted to. But monogamy and non-monogamy are both rampant across the orientation spectrum-this doesn't change because you define yourself as wanting more. It means you should reevaluate monogamy.

If I consent to a monogamous relationship, I'm not going to suddenly sleep with men when I'm bored and use my cravings as an excuse to sneak out of the consent of the relationship. Period. I may ask for a change in the status, however. There's no difference between doing that and doing the same thing with women. In that regard, bisexuals aren't remotely different than monosexuals. The only difference again is the excuse of lacking fulfillment due to gender limitations.

[tenni]

“You state clearly that monosexuals think that a bisexual sleeping around gives them license to do the same, albeit with permission.
I'm adamant that there is no difference and gender shouldn't be an issue.”


Is that what I wrote? If so, no, let me clarify. I don’t think that I tried to guess what monosexuals think?


Being a bisexual means that you are attracted to both sexes. We are prone to wanting to have sex with both genders and monosexuals should not be surprised or shocked if we want to do so. Whatever boundary rules are established should be agreed to by both (without pressure or threats)


Actually, a bisexual should expect the rules to work for both. If it is an open relationship then yes a monossexual should be permitted to have sex as well.


Just a wild thought though.........If the bisexual wants sex with their own gender then the monosexual should also be allowed to have sex with their own gender would really be equal. But they're probably not interested in that if they are hetero monsexuals. If a bisexual wants to have sex with the opposite gender (as in same sex relationships) then the gay monosexual should be permitted to have sex with the opposite gender. (crazy idea full of weak points to argue againsts but it is equal) lol

[jimdawg]

I disagree. If sex with women is ok, both should have that right, or it is cheating with a technicality using bisexuality as an excuse...

[Long Duck Dong]

You state clearly that monosexuals think that a bisexual sleeping around gives them license to do the same, albeit with permission.

I'm adamant that there is no difference and gender shouldn't be an issue.

Truthfully, if I'm with someone who has another "best friend" and wants to "play around" then I feel it is in my rights to do the same, regardless of gender. I have an instinct to spread my seed far and wide, as much of an instinct he or she has to be with people who aren't me, if not further. My orientation has nothing to do with that. If she wants an FWB, he should have one, and I don't think it'd make a difference for most women if the guy slept with a girl or guy-the women who would tolerate me fooling around with a guy at all tolerated me fooling around with women. Those that thought it was gross thought it was just as abhorrent. And that includes bi women who I've been with-you'd be shocked how many bi women reject me on the grounds that I'm bi.

I fundamentally believe that bisexuals are NOT different like stated. The main differences are who bisexuals are attracted to. But monogamy and non-monogamy are both rampant across the orientation spectrum-this doesn't change because you define yourself as wanting more. It means you should reevaluate monogamy.

If I consent to a monogamous relationship, I'm not going to suddenly sleep with men when I'm bored and use my cravings as an excuse to sneak out of the consent of the relationship. Period. I may ask for a change in the status, however. There's no difference between doing that and doing the same thing with women. In that regard, bisexuals aren't remotely different than monosexuals. The only difference again is the excuse of lacking fulfillment due to gender limitations.

the interesting aspect is that what people can want is a open relationship with permission but use the excuse of bisexuality as the reasoning, then can deny their partners the same right by using sexuality as the defining factor..... its a nice way of trying to blur the lines while retaining control.....the idea that bisexuals need to have sex with both genders is used, rather than the *open relationship * aspect as it makes it personal and any refusal to allow that, is immediately seen as wrong and disrespectful of the bisexuals needs and it also effectively cuts off the partners right of choice as well........ its a bit like saying that I need to have sex with more than one person because I am bisexual but you are not bisexual so you do not need to......

the trouble is that its once again, putting up a image of * bisexuals can not be monogamous * and thats something that has rubbed a few people up the wrong way in the site as they are monogamous bisexuals that are pretty much told that they need to shut up, they are not pushing the * acceptable * image of bisexuality that society needs to see.....

the other thing that I have noticed, is that the bisexual female is not being called out as possessive and jealous... yet if she was a heterosexual female, she would have been... as its normally monogamous people that are required as selfish and jealous when they are not open to the needs of the bisexual, but when the roles are reversed and its a bisexual female that is saying no to a open relationship and is reported as being jealous, there is dead silence......

I pretty much agree with you..... bisexuals are not really that different to the rest of society and humanity, their thinking, reasoning and motivations are the same as the rest of the human race, its the need to put bisexuals into a class of their own and put bisexuality out there as only something that a bisexual would understand, that is the problem...... the interest in non monogamous / open relationships is a human aspect, not a bisexual one....and like any relationship, a compromise needs to work for both people equally instead of the * I have to cheat because I am bisexual * argument that is used so much......cheating is not a bisexual aspect and never has been, its a choice made by people using a reasoning to justify their actions

[tenni]

I disagree. If sex with women is ok, both should have that right, or it is cheating with a technicality using bisexuality as an excuse...


I agree with you and so I'm not sure what you are disagreeing with? If the bisexual can have sex with someone else so may the heterosexual. Inorder to be equal though, the gender of the person should be the same as each fiancé. It is not using bisexuality as an excuse. It is equality.

Another option is to have an open relationship is that they both may have sex with anyone regardless of the gender. That is ok as well as long as he can handle her having sex with another man as well as a woman. She can handle him having sex with a woman and a man.(should he ever want to)

As far as cheating is concerned, if they agree with the boundary rules then it is not cheating.

[jimdawg]

But that isn't equal because it just so happens that only one person in the relationship can actually have sex with someone not in the relationship...it is, rather, a set of rules you want to have of semi-openness...while allowing the partner to be bisexual for one of two reasons: either you want a partner to be like you, or you don't want to feel guilty at the fact a relationship is inherently unequal.

The open relationship is the equality part. I agree that someone should be comfortable with someone in the open relationship having sex with someone regardless of gender-that's the point. But to somehow pretend that, if you're with a straight guy, that you should be allowed to sleep around where he isn't, or if you're with a lesbian and you should be allowed to sleep around when she isn't, that's not equal. Like, trust me, I want a bisexual woman for the reasons you basically state, but in my experience with dating, it is far easier to allow the girl to pursue bisexuality than it is for her to allow me to do the same. And I've also experienced the "Why are you concerned? Shouldn't you find that hot?" argument.

The reality is, a genuinely straight guy won't have sex with another guy just because you have sex with a girl. If it is monogamy, then it is monogamy, and you shouldn't have sex outside the relationship. If it isn't monogamy, that's another story. But to somehow pretend that a bisexual is allowed two lovers and a heterosexual/homosexual has the same right (but will only take one) and say that is equal is simply greedy. And that sort of annoys me in the sense that I've wanted to date bisexuals who were identified lesbian, but wouldn't date me due to the fact they'd be rejected by the lesbian community for being "Greedy"-and I think this justifies certain biphobia, that the bisexual will never commit to you as they'll always desire the opposite gender of you (I've been rejected by women who were in fear that I'd always want to SECRETLY take a cock behind their backs and go out and do it-even though that's never been an issue in practice; I mentioned a girl who turned out to be gay? She was cautious on me cause she thought I was the gay one...).

And thus I will say adamantly if the girl in the OP's post is jealous of the notion of her boyfriend dealing with women, she shouldn't be dealing with women. If I'm in a monogamous relationship with a woman, I don't take cock. Period. It is self control. I might like and crave it. And frankly, I'd probably avoid a monogamous relationship for that reason. But if I'm in one and committed...it is my word of honor. And I won't defer to being a bisexual to escape what I've entered.

[tenni]

"But to somehow pretend that, if you're with a straight guy, that you should be allowed to sleep around where he isn't, or if you're with a lesbian and you should be allowed to sleep around when she isn't, that's not equal."

I think that I understand what you mean but I don't think that the woman is asking to sleep around. She seems to be more interested in a closed loop relationship but I could be wrong. Sleeping around is not a closed loop relationship. In a closed loop relationship the bisexual has one partner of their gender and one partner of the opposite gender. The same gender person may also be in a cross gender relationship as well. There are no others. It is not really an open relationship. I suppose if they hit it off the two monosexuals could have sex with each other as well.

"if the girl in the OP's post is jealous of the notion of her boyfriend dealing with women, she shouldn't be dealing with women."

I agree that the bisexual woman seems to have some jealousy issues but you are referring to apples and oranges here. I suspect that we shall have to agree to disagree.

I think that what you are posting as being unfair to the hetero is written from a more monogamous low same sex need perspective. This is not your problem as you do not have as strong a need to be with same sex partners as the woman and other bisexuals. There are several forms that heteros may have a relationship with a bisexual.

[jimdawg]

Sleeping around in my opinion is a closed loop relationship if it isn't even; if the guy doesn't have a secondary in this case, it is "sleeping with twice as many people as him" no matter how you slice it, which is by default not equal. It isn't agree to disagree, it is a fundamental difference. You benefit off this type of relationship, whereas the person in the relationship does not, beyond the fact they're in a relationship with you. I agree that you can consent to have it, but to somehow put it on some different morality...I find to be perverse due to the fact it is inherently not equal, and almost always to the person you deem the monosexual. Slice it any way you want, this is still the issue I have. I don't mind these relationships existing at all. I definitely mind these relationships somehow being deemed more "OK" than other sorts of non-monogamy because the "needs of the bisexual..."

If you can't see how this is inherently selfish as an attitude, I don't know how to make you see that. Perhaps no one has used you to cheat on their lover before because of something they haven't gotten. I've been used for this purpose because I wasn't a woman, which at the end of the day feels no different than being used for this purpose because I simply have a much bigger dick than the boyfriend of a woman that used me for this purpose as well. But ask anyone, man or woman (or transgender), bisexual, gay or straight (or queer), who believes in monogamy, ethical polygamy exactly what the difference between a man and woman is on this situation. I doubt off of a bisexual forum with a lot of sexual fantasy you'll find too many people who disagree that sleeping with someone who isn't your primary is a form of seeking secondary sexual relationships, which is an open relationship, and demanding they be bi if they wish to have a secondary is just a nasty way of degrading them.

[Gearbox]

The OP's gf's problem is that she uses jealousy as an excuse to have different rules to the OP. She wants a female FWB due to her unsatisfied bisexual curiosity, but her selfishness is due to jealousy and possessiveness towards the OP.

Bisexuality is used as an 'excuse' to have more than one sexual partner, no more than jealousy is used as an 'excuse' to be sexually exclusive.
In the OP's case his gf is both bisexual and jealous. Her jealousy is what's causing the friction in the relationship, as it always does, and her wanting for herself what she denies the OP is the selfish part.

[Bitten]

How a about a compromise? She works on her jealousy and honesty issue and OP works on his rules. Since she is new in town and wants a friend, maybe both of them could search together for a friend they are both comfortable with and would like to hang out with. She wants sex with him not in the room but he wants to watch for his pleasure, maybe if they find the right person, they would agree to filming and he and her could watch together later ( since she enjoys girl on girl porn it would probably be a big turn on during sex). Just an idea.

Would have to agree with gearbox about her jealousy. However, we only have his point of view on things. I think op should encourage her to join and post here. She should not have too much problems with that if she is already using other bisexual sites.

[The Black Knights]

Confusedfiancee,
You have a tough situation. Your soon-to-be-wife sounds like she wants to at least try to have sex with another woman, but she wants you, too. I understand that you are a straight man, so consider it from this angle. What if one day, you became bi-curious yourself? If she is bi-curious and you continue to insist on being physically being there when she explores this with a virtual stranger, she will either do it behind your back, before and/or after you marry OR you will lose her altogether. Her jealousy about you and other women is not unusual, but it can be a problem if a woman you are attracted to was attracted to him as well and tried to act on it. I am not fond of jealousy in a relationship anyway, but you have to compromise.
I know from experience that a woman (or a man) who is bi-curious (or truly bisexual) often wants to try that first time (or most or every time with a woman) alone. The other partner who may or may not be more comfy with such may well insist on such. You have to let her do so. For all you (or she) knows, she may do it and decide that she doesn't want to do it any more and then be happy to just be with you and never do a threesome. If so, problem solved. Threesomes are not as easy as it looks. I would say to you is to let her try this thing alone and say nothing. But here is the compromise: She tells you everything that occurs and you discuss your (and her) feelings openly about the experience. I would also add that IF (in the unlikely case) you decided to become bi-curious yourself, she has to do the same for you, with the same conditions. That way you are covered.
I don't feel one party should be able to do one thing in this area and the other cannot, for whatever reason, even if the other person never chooses to act on it. Lastly, if she is to try this, she must do it BEFORE you marry her. If her possible bisexuality, much less the possible interests in threesomes or whatever else from either or both of you is to be explored, it is better to do it before the wedding and the feelings that come from such activities because if any of those things is a deal-breaker for your relationship, it will be far easier to deal with such and decide what to do if you are not yet married versus after you say "I do". Trust me on this, love can conquer all, but especially in this day and age, you have to be practical too. Feelings matter a lot, both yours and hers.