I've been stopping at my dads for the past 13 weeks. Had a rough time of it so had a few drinks last weekend and ended up having sex with my step brother. I didn't mean for it to happen and he came onto me. I feel guilty enough as it is because he has a girlfriend and kid. Although he was already fighting with her.
But now his mother has found out and she's not happy. I really don't know what to do. It won't happen again and although I do fancy him i have reassured her i would not do anything again unless he was single. 