This is weird and depressing, but fascinating too:
She's a successful law professor and a Sunday school teacher, with a host of family and friends. But her interpersonal calculus centers on how to manipulate and outmaneuver the many people in her life. Welcome to a world of ruthless cost-benefit analysis, charm, and grandiosity.
..For as long as Lucy dated Cass, I kept him as my sidepiece: I would induce him to make and then break dates with her in favor of being with me. He knew I was using him to mess with her. When he started to feel pangs of conscience, I broke it off with him. I waited until he focused all his attention on Lucy, waited until she got her hopes up, then I called him again. I told him we were meant for each other and I was just testing him.
Lucy made things worse for herself—she had no sense of keeping personal things private, particularly from people like me who could use the information against her.
also check out M.E. Thomas' website, SociopathWorld