Hi Rosie, 
Welcome to our forum.  i'm glad you found us and shared your situation and questions. 

There is no "for sure" with any of this because every human being is different.   It is entirely possible that your partner is Bisexual and enjoys both men and women.  Or it's possible that he was gay at one point and is now into women only.   BUT..  that is not the experience of most of the people in this forum.   For most of us, our spouses lied to us about their sexuality because they didn't want to be gay.  They didn't want the world to see them as gay.  So they try to find a woman or man to marry them.  They try to be straight and live a "normal" life.  But most of us are here because we found out that they couldn't make that change permanently.  We either caught them cheating or they found a gay/lesbian partner and left us for them.  

In my experience and opinion, sexual attraction is not a choice.. it's something a person is born with.  That means that no matter how hard they try they can't be attracted to the opposite sex.  They might have hetero sex, and early on it's exciting just because it's sex, but it won't be completely fulfilling and over time it will languish and go away.  

Rosie, 
Are you willing to take this risk?   Do you love him enough that you can trust him to be true to you for the rest of your life?  Are you willing to risk a sexless marriage?   Are you open to him being with men on the side and having an open marriage or having 3-somes or other adventures?  Do you really believe that he is no longer attracted to men?  Do you feel his angry reactions are evidence that this is something he is comfortable with in his life or is it perhaps a topic that is still burning inside of him. 

Rosie885 wrote:

When we first got together he was quite honest and mentioned his like of BDSM and I was very open to that. It was interesting how once we fell in love he hasn't been interested in that anymore. Not even with porn. Any ideas why that might be?
 

Was he quite honest about BDSM only or was he also honest about being with guys?  Seems like that's the bigger secret sexual intrigue and something that if he was truly honest he would have talked about.  If you only found out about the gay thing by an accidental drunk incident then this would be a big red flag to me. 

I don't know much about BDSM.. not my thing.  But you mentioned earlier that it had to do with being submissive.. which is probably mimicking his role with another guy.. ??   I wonder if he thought that would be enough to satisfy his urges, but has found out that it is not and now no longer asks for it?   I really don't know.. just hazarding a guess at this point. 

You are right about being unique in that he told you everything in advance.  That is a good sign.  You should also keep in mind that most of here were burned badly and hurt severely, so we tend to form our own opinions based on those very hurtful prior experiences and we tend to be very mistrusting of those who display similar traits of our ex's.  

I think you are on the right page about talking with him further.  If he truly loves you he needs to be 100% honest with you.  He needs to care about you more than himself and be willing to let you go if he thinks there is a likelihood that his former attraction to men would cause issues in the future.    I say this often about my ex..  "If she really loved me she would not have married me because she knew in her heart that she wasn't attracted to me.  It was very unfair of her to hold my life ransom on the chance that she might be able to overcome her lesbianism".    

Please do..  and stay tuned for more people to chime in.  I didn't mean to dominate the conversation..  There are lots of us on the forum with different perspectives and amazing advice..   pop back in and let us know how things go and see what other folks here have to offer.