Mixed signals...

Hey everyone! Okay so for a while now me and one of my male friends started messing around and all.. I really like him, I'm pretty sure he doesn't feel the same for me considering he's still in love with his ex(they haven't been together in a couple of years lol) but what confuses me is that he'll spend every waking moment calling, texting me, trying to hang out, constant sex.. Like what can I say or do or even feel!