I Was Cheated On

My girlfriends other lover saw us in the pub on Friday night. She thought I was the other woman and we all had a big argument outside. In the space of a few weeks I've realised I'm gay become secretly & romanticly invovled with one of my best friends who has now cheated on me. I haven't had the courage to come out yet so there are only a few people I can talk to about this so i just want to get this off my chest.