I would suggest counseling. It will help to be able to talk with someone who isn't intimately involved. Learning some better life skills, and learning how to focus on healthier things.
Another thing is for you to realize that you are SOOOO much luckier than is he: psychopaths, sociopaths, live in a Hell-on-Earth from which as of yet there is no escape.
Counseling is good, and so is the gratitude that psychopaths are out of your lives. However, there are many legal ways to get revenge with them.
First, because they are narcissists, you can threaten their reputation in ANY way. Also, they are notoriously shady so there might be some criminal activity, which you may have information about, that could get them in trouble (which they deserve.) Lastly, I think they are paranoid. For this reason if you plant the seeds which make them think you want revenge, well, they worry. They worry a lot. You might as well play the mind that played you!