I agree that it's pretty natural to have these feelings Woodman. I remember your story but I went back & re-read a bit just to refresh my memory.
All I can say is that she failed at SEVEN detox attempts over 10 months..... if that didn't make enough of an impact on her then how could moving home have helped? Your head knows this but your heart is going to need some time to fully accept it. Just remember how we say around here, "Feelings aren't facts"..... just because you feel that moving home may have helped her doesn't mean it's true.
FWIW I think you are a ROCK STAR of a Dad. When it came down to choosing whether to sink/drown with AW or throw her a life jacket & row that lifeboat to shore with your kids safely inside... you made the right decision. Your kids will thank you for the rest of their lives in a million healthy ways for making them the priority here.
(((((((((Many Hugs)))))))