FT,
I agree with you about the separation vs divorce. My therapist told me that separation means nothing. Even if you filed for divorce and he "finds" God and gets well, you can always put it on hold.
I am 1 1/2 years post divorce. Given up hope that AXH will ever find sobriety. Grateful every day that I am not on that crazy train anymore.
Sending hugs to you, it is painful, but you can do it.