I've been having this problem with my ex- obsessing over what has been and what could be. We have completely different goals and ambitions and I'm actually the one that broke it off with him. I'm not OK with being with someone who doesn't seem to have any dreams and I know that I can't change people. I know that he is not a man that I want to be with but I still have this empty feeling in my stomach that I assume I have because I miss him. Why? Self esteem? Just missing cuddling in bed? Why do I miss him soooo much? I've had this problem with every ex I've had. I'm so much happier when I'm single. When I'm in a relationship I have no self confidence, I'm anxious all the time, I've lost balance. I just want to feel what my head is saying.