I haven't spoken to my now XH since the night he walked out (October 11 2015) and left everything behind.
If we were ever to be in the same room together again (we sometimes work in the same industry), it wouldn't even register that he was there, it would be like he wasn't in the room, and I would act accordingly.
I wouldn't ever speak to him again. There are only a couple of people who fall into that category for me. He is one of them.