Here's my quick response as I am at work right now, LOL.
First, I detached with anger and had to work through resentments, unforgiveness(my own), and martydom crap that I was carrying around with me.
Then, I detached with love once I took ownership of what was mine to work through and what was my part.
Then, I was able to let go. Truly let go: no resentments, no hard feelings, no anger, just compassion and love from a detached distance, respecting him as the father of our son and letting him walk the path that God has put before him.
Today, my XAH no longer takes up any of my mental energy. There are no more obsessions about him or about his drinking. I find it amazing that I don't think about him AT ALL after being married for 20 years to him. The only time I think about him is when I need to ask him about child support, about whether he can take our son somewhere, etc. As far as how crazy in the head I was about him last year, that is all gone and it was truly a God thing, a spiritual awakening, and a process from both using Al Anon and all my support tools along with 3 years of therapy.