I often see the coldness, cruelness and ignoring behavior get worse when someone has ended a relationship and moved on and the other person is still trying to hang on, still wanting to be friends still wanting to remain a part of that person’s life. Break ups are hard and painful but as we always say around here it’s their actions not their words. He has ended the relationship he has moved on to someone else and that is very hurtful and hard to accept. And if you continue to try and be a part of what he’s already let go of, of course it might fuel anger on his part.
He cannot be nasty to you if you do not let him. No contact = no new hurts!