I need help with my past relationships!!!?

Ok Im in a relationship with this guy, and he's great couldnt ask for more. But lately I keep thinking bout my exes. My most resent one I miss lil things he used to do, but he cheated so bad on me (would never admit it but I knew) reguardless, then my ex hubby, (which I have my 5yr old with) things just didnt work we are great friends now, but my current boyfriend mentioned that if he would have a kid with someone then it would have to work reguardless. So it makes me think that maybe Im in the wrong. Plus my ex hubby just moved in with this girl after datin her for only a couple of months..... I know I dont want either of them back, I have a great guy but I dont know why I cant let go of my past, stop comparing, and just be happy.