I'm not going to talk with my ex-bestfriend
Why would you stop talking to her? What happened?
He falsely accused me of shit
It's understandable to cut off communication with someone who used to be a friend, but you should tell them why. Otherwise they may keep trying to communicate with you.
I'm just going to ignore him.
Ignoring them might be the best way to go about doing things. If you confront this person it may cause more issues for you down the line.