BR, I have a story of trauma and abuse that is approximately 100 pages long (single small text). I think that explains part of the addiction process... maladaptive coping skills... however, it doesn't explain my euphoric reaction to alcohol that other normal drinkers do not experience.
I don't want to undermine what you went through in the rehab, but I think addiction is more complicated than what you have presented. Well, at least for me it is.
Levi