Is it possible he has actually dried out enough in the last couple weeks that he is seeing his past behavior through a sober lens?
Being as fucked up as he has been for the last couple years, then seeing yourself and your past behavior with a sober mind can be soul crushing. The guilt of what he has done to his kids, to his marriage and to his career may be slowly seeping in while he struggles desperately to keep his ego intact.
I have to believe he has been keeping to some kind of drug rehabilitation program to get his kids back? If he is not completely sober, he is definitely far more lucid than he used to be if he is only keeping it to occasional drinking.
Or he is still getting wasted on the regular. In which case, forget this.