Relationship advice - is my boyfriend gay?

Me and my partner haven’t been together long however we’ve been good friends for over two years and it was only about 5 months ago we decided that we both had very strong feelings toward each other (he made the first move). We have been going really good in a relationship and he makes me so happy and would do anything for me. I’m 100% in love with him and he says he feels the same towards me. So anyway, he goes out to the pub usually on weekends with his friends and always lets me know he is safe and will usually come to stay with me the same night. However this weekend he went out and hardly contacted me at all and got so drunk he passed out at his friends house. So I finally get hold of him around 9:30pm on Sunday evening and he sits me down and says he needs to talk...... He said that he wanted a break which I was fine with, everybody needs their own space. But then he continued on to say that he was gay and that he had kissed his first ever man when he was drunk over the weekend. I need help to understand what to do? I am giving him space as he wishes and he says he still has feelings for me. I love him so much and it hurts me to think that our relationship will have to come to an end because his attracted to men. Also we have an amazing sex life and his never shown any signs of not being interested in women. Does this mean his bisexual or is he just confused after a drunken night out? What things should I do to help the situation? I want to help him as much as possible and I will support him no matter what, I am just confused and need someone else’s opinion as to what this could mean and what to do.

Thank you for your reply, I think I would be okay with it, it may make a relationship more difficult however I would be willing to try to see if it could work. It’s not that I find it hard to believe it’s just a little confusing considering it has come out of nowhere. I believe him as it did take him a while to fully spit it out and it doesn’t seem like something he as a person would lie about. We are both very honest and truthful with each other and we always have been. I love him to bits and it’s hard for me to get my head around. I am giving him space to figure his head out and I want to be as supportive as I can with it. I’ve been in some long term nasty abusive relationships and this one has been amazing which is why it devestates me so much.

what I’m trying to say is that if we did decide to carry on the relationship I would be fine with the fact he is bisexual however it would make things more difficult. I don’t want to not be in a relationship with him but I that would be up to him in deciding what he wants (depending if he is certain he is gay or not) I couldn’t ‘share’ him because then there would be no point in being in a relationship. To be honest I am just very confused and I never thought I’d be in this situation, I just wanted someone else’s opinion on what they’d do or if it’s worth trying to work things out? If he decides he doesn’t want a romantic relationship I’d still want to be friends as we have been for so long but I don’t know if that’d be healthy for either of us?