Thinking of another man

Ugh omg so ive been with my bf for 2 years but we broke up for a while not even a week n i hung out with some guy i used to talk to before i was with my current bf. The breakup happened last year during the summer n i got pregnant in august n my baby is now 2 months but i cant stop thinking of the other guy. I fantasize about him n ugh idk he wanted to be with me but i stayed with my bf because of the baby n so far were doing better but idk why i keep thinking of the other guy 😭 we did have sex before n i keep thinking of that n him n idk what to do. No hate just wanted to let this out 😵