Heart or mind?

I was with my ex for about 10 months and then I began to like other guys and soon enough, I guess began to "loose feelings" for my ex until I actually stopped caring. I was off trying to meet new guys. They all treated me badly (which is a reoccurring thing for me). But sometimes when I see my ex having fun with friends and standing by girls, I feel hurt. I try to turn away but it's on my mind.I tried dating my ex again, but things changed as in I get annoyed more, etc and my whole self isn't focused on him rather mostly on "other guys". Yet sometimes, those warm feelings for my ex come.. sometimes they do.. and his pheromones get me. Ha. Well.. I don't know. I'm known for dating a lot of guys since I guess I am obsessed with the high of infatuation. Me and my ex aren't infatuated anymore. It's more realistic. I guess the other guys are something NEW. Something "not there for so long". I've been molested and funny how relationship problems are exactly like mine. :/ And guys have hurt