When I left my AH, one of my friends told me "you might have just done him the biggest favor anyone will ever do him in his life, even if he doesn't see it that way right now."
Five months later, he has been sober for five months (minus 24 hours), he's developing healthy friendships, and he is a better parent than he has ever been.
It's a hard road to travel, but you are doing a good thing for everyone involved, and it's up to her if she wants to take the opportunity she has.