Most Helpful Guy
Seems like a pretty confusing guy to be with. i feel like there's some things that you aren't telling us (i will respect yer privacy doe) but all in all, just don't do it. It's immature to do something like that. Let it go, if you truly are angry at him for leaving you, then let it go.
Don't waste time trying to get revenge on him, focus on the things that are most important, you. If you know yourself well, then you know that you're a woman worth being with, you don't need to make him 'regret' just to confirm that you're worth something.
Everyone is always worth something to the right people.