Deadtome been there too and I truly get it. It's shit and unfair.
It's normal to want revenge so don't fight the anger just don't act on it. Dignity is your best friend.
Personally, I found locking him out of my feelings was the best revenge. He had several honeymoon periods with new girlfriends after the split, between which he tried it on but couldn't get past my magic force field of indifference.
They don't like not being able to read you, they really don't.
Also, when the mask slips, as it invariably does, those who don't know yet will see him for what he is. But who cares anyway.
Gradually deciding not to give a fuck about him or waste any of your precious energy thinking about him will be your best revenge.
You can create a lovely atmosphere for your DC without him. I found channeling the anger into DC activities helped. Lots of cuddles too.
Wishing you lots of strength, I know Christmas can be a hard time. You will get past it though.
People like that are never truly happy, whereas you can look forward to that without him. So in a way, his personality will take care of the revenge for you.