vagillate

Verb: vacillating between the same few exes; a girl that keeps going back and having sex with the same few exes.

A friend of mine was married to a guy and got divorced, started dating a new guy, broke up with him and got back together with her ex-husband, broke up with him again and went back to the "new" guy. She calls it recycling, we call it vagillating.

Jane continues to vagillate between Joe and Bob; she really needs to move on!