The ONLY thing I have judged you for is saying that your child made the decisions. It is fairly clear from your story that he didn't have a choice. You yourself said that. Just put the blame where it seems like it belongs... on your ex. Not on a child.

I am so sorry you have had to go through something so horrible.

I myself lived through something similar as a child. (If you don't believe me, I have written some about it.) My mother has never once said that any choices I made due to the manipulation of my father was my fault even if those choices hurt her. Now that I am an adult I can see my mistakes, but children don't have the foresight that comes from experience. And a parent that blames them when they were in a catch-22 wounds them deeply for not understanding that. And wounds like that are hard to heal and recover from. I pray that is not your situation.