I think I love my best friend. But only when he is dating another girl. When he is single, I lose all interest. I enjoy the thrill of doing things with him when he is in a committed relationship. I feel good that I can make him cheat. Then, when he is single, he wants to get serious with me, which is a big turn off. So I just dismiss it by getting a new boyfriend and saying "sorry". Too late. I feel like I'm going to lose my best friend over all of this. He is continually distant, and not wanting to hang out alone. Mainly because he knows what will happen.(what always happens). Is it normal that I act this way? Or do I need help?