The Sociopath Of Least Resistance

I discovered that the guy I'm dating has a girlfriend he's cheating on. In fact, she confronted us, which was awful. I've had a history of guys cheating on me, and I want to end the pattern. Unfortunately, I'm not attracted to a lot of guys I go out with, and I'm really attracted to this guy.

--Chemistry

Being really attracted to somebody is the go-to excuse for shrugging off a potential partner's shady behavior -- pretty much anything this side of "Well, sure, several of his neighbors are...