Bubba, the first thing you need to do is cowboy up.
Then call an escort service and lay down some coin for a seriously smokin' hot gal, and get photos while she's taking a long slow ride on your baloney pony, blow 'em up and mail them to the witch. Then throw it back in her face every damn time you see her.
Either that or stay a weenie all your life moping around the house because of this girl.
This actually is sound advice. There are many ways via the internet to get hooked up. It will ease the pain. Focus on your freedom! If she does come back to you in a few months make sure the sex is rough and hard. She deserves that at the least.