So I've been kind of on again off again with this guy for about 2 years. Mostly on, but for the past 6 months we've just been fwb after a pretty bad break up. The other day we were hanging out (we hang out without sex sometimes) and he asked if I ever thought about getting back together. I said I tried not to, and he said he has thought about it. So today, I asked him what he meant by it and he said that is and ongoing thought but we can't get back together right now. I also found out that he kissed another girl the same morning when he asked if I thought about getting back together. 
I'm completely In love with the dork and don't know what to do because I don't want to lose him.