I think my boyfriend is struggling with being gay which creates moodiness.

Gay Issues and Problems

My boyfriend has admitted he is bi-sexual. We have had threesomes with other men (he prefers men) which is fine with me. I am fine with that part of our relationship but I am concerned that he is actually gay and is denying it. I have come out and asked and he has said "no". He is very emotionally abusive with me. He is very moody. One minute he wants to get a house and move in together the next he says "I don't know what I want". He used to tell me he loves me and now he won't because he doesn't want to lead me on. He seems to go through a PMS time monthly and when he does that is when he gets all weird then a few days later he is all over me loving, huggy, kissy. I feel like he is struggling with himself and goes through times when he is angry at himself for thinking in a gay way. It is like he has a good bash on himself then it is over and he says to himself "I am fine, I am not gay, I am all man and want to be with my girlfriend". His best friend says he sees gay tendencies in him. He has no ambition to move forward in life...he just says "I don't know what I want and don't pressure me". He is 31 and lives in a dive apartment and smokes pot when he is not at work. He has the opportunity to have a house etc. but just won't make the commitment. He knows he has a problem but he says he is a sex addict. He used to have a computer but he got rid of it because he knew it was ruining our relationship because he was on all kinds of dating sites and gay sites but he aways said he was looking for "us". He has been in many relationships with women but then he says he gets bored with them and wants a change so he ends it. He has been with men on his own before we met.
Please tell me what you think on this. Should I leave him or try to work with him on this. I have never loved anyone so much ever before.
Help Please