I have not actually obsessed over a certain person, but I have obsessed over the thought of being with someone else just for the sheer passion. I like the bad boy persona and I don't want to make a relationship out of it though. I am married and I did mess up once, but we were having major marital problems and I was about to leave him, not a good excuse though. I still have those thoughts but I try to actively to reorientate myself when I get those feelings. Therapy helped me a lot in developing coping skills. If you don't see a therapist I would recommend you to find one.