Do you think I should ignore my ex?
Why would you want to ignore him?
I want to prove to him he can't mess with me.
I think that's probably for the best.  It's good to just move on from an ex rather than remaining involved with them.  If you keep in touch, there's always the potential for getting hurt again.
I agree. The last thing I need is to be messing with an ex.
It's good that you realize that you should move on. I'm sure you'll be much happier when he's out of your life completely.