How Can I Avoid Being A CRAZY Ex?

We all have that ONE friend who maybe takes a breakup a little too hard. That friend who doesn't want to admit that it's over. The friend who maybe is a little too concern what the old ex is up to. The friend who wouldn't mind if his or her ex were to be incredibly uncomfortable for a while. That friend. Sure you'd never do that, but how do you help your "friend" from becoming that person again? Helen Fisher and our panel of experts have advice.