Aw, man, I'm so sorry. That just sucks all around. It hurts because of the mental anguish you went through with him. It sucks because it's a double betrayal in a sense (or is based in that from the past).
1. Kill them with kindness. That doesn't mean you're a doormat or that you talk to them or connect to them, but if they do contact you, be as classy as possible. Rise above it.
2. The pain will go away over time.
3. It's a great time to detach even more. Do what feels right for your own personal health.
(huge hugs)