What exactly about this guy that you miss? Was it him or was it an ego boost or feeling? Was it the sex? Was it the money? What did this guy have that no other guy in this world possibly cant do it better?
Its been 2.5 years since the break up. Doing the same thing you have been doing for 30 months isn't going to help you. As Holly suggested, I would seek counseling. Maybe it has to do with something with a loss and nothing to do with your X what so ever. Have a professional help you sort out your feelings. You will thank yourself for it.