Posted once can someone give me advice?

Lately me and boyfriend have been going through a rough time, I cheated on him when we first started going out and he forgave me, and the 3 yrs later I duno what triggered it but i started feeling guilty about lil details of what happened when i cheated and ****. I told him most of it ya know but i just keep thinking about lil things like what was said between me and my ex when i cheated on him. I also found out that my bf cheated on me 2 because he said he thought it would make him feel better about what i did to him but he said it didnt. Anyway I feel like everything that happens like when i go to a store or whatever i cant even look at guys, not like look at them for prospects but just happen to look and think someones attractive. ya know like when u just see someone in a store & think there cute & keep walkin i feel guilty about that kinda stuff. And i cheated my ex that i cheated with tried on my school sweatshirt and i didnt tell my bf that, he said hes tired of hearing lil ****.