Background: I have 2 kids with 2 diff dads. “A” was my best friend in high school and we dated throughout college and I had our kid my last year. He cheated while I was pregnant and we broke up. He was and is VERY active in our lives.  I got with “B” when my first kid was 1 and helped me heal from the mess and a relationship developed.  We had my second (and last) kid during our 8 years together. This entire  time “A” would always go out of his way for my kids and I,  regardless of our other relationships, causing me and “B”to break up and the break up of his relationships. Plus “B”is a functional alcoholic. For the last 2 years, I have been sleeping with “A”. I keep wanting to find a meaningful lasting relationship but we keep getting in our own way bc we still sleep with each other frequently.  I am completely turned off by “B” and his issue so sleeping with him will never happen again. The attraction between me and “A” has always been strong enough for others to feel it.  My question is, knowing I have trust issues due to him cheating over 10 years ago, why can’t I stop sleeping with him?