I've been in exactly the same position 4get;
After being spectacularly cheated upon we break up and it takes me a month before I can afford to move out of his place, during which time he is off galavanting with his new totty. A couple of times he's at home and after a few drinks tries to flirt with me. Shocking! I since moved out and sporadically get texts/calls from him about insignificant issues even though I made it clear that I want no contact. I ignore every single one of them. This happened up until Saturday night when I pick up a voicemail message from him accusing me of stealing his DVD's!! (I haven't) and I can hear his new woman in background rhyming off which ones he's meant to tell me about. That's the final straw for me and I finally text him back in a calm but horribly sarcastic manner and make it perfectly clear what he can do with his DVD's!
It's outrageous behaviour. It's purely a control thing. He doesn't have a say in your life anymore and he probably hates that you could be remotely happy without him.
At least you can take comfort in the fact that you got out! If he's anything like my ex then you've probably realised through all of this just how much of a lucky escape you've had. I found out recently that my ex is registered on adult dating sites, even though he's seeing this new woman!