How do I get over this pain and confusion and embarrment?

I read recently that love acts on the brain in the same way drug addiction does. I don't think this was actually love -- more like infatuation, but anyway, it sticks with you. You feel like if you can just get his love in return you'll feel good again. The same way a drug user keeps looking for the next fix. So now you're in withdrawal. Part of you knows he's not good for you (that's the relief) but another part of you still thinks there's something you can get from him (that's the sadness). Make an effort to keep him out of your thoughts. Don't contact him at all. Don't go checking his facebook page. In time the feeling will get less and less until you can't remember why you were so crazy about him.