How do i talk to him about it?

I've been in love with my best guy friend for nine months. I had my chance to make a move, but i had a boyfriend i was staying loyal to at the time. When the both of us were single, my best guy friend wasn't getting my subliminal hints and thought that I wasn't interested in him. So he went to the movies with a girl and did some nasty things with her. He was intoxicated so he of course regrets it to this day. He has a girlfriend now and they are pretty committed. We've told each other that we like each other. But he does nothing about it because of his girlfriend. It pains me deeply to not have him. I have a boyfriend too, but i don't feel a strong connection between us. How do I tell my best friend that i'm in love with him? Should I even bother?