Help! I don't know what to do ?

Me and my boyfriend dated for almost 4 year. our sex life was always not that good. but we loved each other so much. but in the last year we had so many problems and I broke up with him. When we broke up, I met this guy. and OH MY GOD, the sex was Amazing!!!. we would have sex for hours and hours. like 4 times a day.

Then my boyfriend kept trying to get back to me and him and the other guy did so much to prove to me that they care for me and each one wanted me to be his girfriend. at the end i decided to go back to my boyfriend because I felt like I still have feeling for him.

but the problem is that our sex life is so bad and I can't stop thinking about the other guy. I feel so guilty because my boyfriend is so nice to me but i keep thinking about the other guy all the time.

me and my boyfriend got back together 2 month ago.

how can i love my boyfriend but not be attracted to him sexually?!

What should i do