One way to find out if he is gay is the following. Gay men, as opposed to heterosexual men, are always looking for who is watching them.
And, gay men are usually a pleasure to have a relationship with. I know that from my own experience. but, it's hurtful for you, and especially if you are not aware that he is gay, because you may think it's you, and it's hard not to take this personally.
I would vote for gay too. I don't know a straight man that does not want to for intercourse with a woman.
this is a real hard one. you love the guy.. but your not haveing no sex.. wow.
if you love him oh well.. what areyou going to then? good luck.
If he really feels that way towards sex with women, and thereby you, I think you should look for another boyfriend and keep this one as a good friend. It's too damaging on you not to be desired at all, I think.