TL;DR: Me [20M] and my girlfriend [22F] of 3yrs have recently gotten back together. But after quite a bit of thinking, I've realised I'm gay. I have 2 stepchildren with her, and I'm at a loss of what to do. 


At the start of our relationship I was out as bi, and she knew that. Things have been up and down for the past year and a half. We had a break last year and in that time I had sex with 2 guys. Which she knows about. We recently had another split, and I told her that I wasn't in love with her anymore, which is partially true. It's only recently that I've become fairly certain that I'm gay or bi with a very strong tendency for men. 

We said we would try again, but at this point I'm not sure how to tell, I wish I had realised sooner, she's my best friend, and all the family I have and I just don't know what to do anymore, because I don't want to hurt her anymore, but I know she isnt going to take this well after all the problems we have had over the past year and a half. 

Please help. 
