When I was about 14 or so, I briefly dated a boy from my high school. It wasn't serious and I never would have been so stupid as to have sex with him, but he cheated on me so I just sent a bunch of negative energy his way and the next week he came to school with a broken arm, a wrecked car, and a dead brother.
My ex has screwed me over. A couple of times. First, when he kissed me while he dating another girl, and now, when he broke a promise that he was going to date me again after I waited six months for him.
Wondering what I did?
I forgave him. I wished him the best of luck with his new significant other, and I'm trying to move on with my life. The best revenge is living well. Not to mention I told him he now owes me, so if and when his current relationship ends for whatever reason, we're going out. Oh, yes.
Congratulations. He's a douchebag, and you're a manipulative sociopath. The best revenge would have been you growing as a person enough to not make the person you are dating your "everything", than finding someone who treats you right, and hearing about how he did the same to her without your involvement someday when you no longer care.