You are doing what you need to do for yourself and your child. Good for you! You set your boundary and stuck to it. Way to go!
Try not to let your sympathy for him get the better of you. Of course you hurt for him - you are a loving person and you care about him. But as you well know this is HIS problem not yours. I have been trying to teach my son that his choices today can affect his life forever. He doesnt get that. VOP is not going to go away and he knew that he had that charge - he should have taken care of it before now and it was inevitable that he would get picked up - traffic violations is how most VOPs are found so anytime he got in a car he knew he may go back to jail.
I hear this all the time where someone is trying to get their life together and doesnt realize why the past keeps coming up. They think its unfair but its really not unfair - just because you are trying now doesnt mean that the past just goes away. We all have to live with our past mistakes - addressing them before they become problems is the only way to ever really move forward. Can the pregnant teen just take a vow of celabacy and the baby just goes away? of course not - and its no different for our addicts - just getting clean doesnt make all the past go away.