I wouldn't let myself suffer and be abused, lied to, stolen from, manipulated and disrespected for 5 straight years while she was on her alcoholic and pill-addicted rampage.
This is not to say I wouldn't have helped, I wouldn't have loved, and I wouldn't have tried my damndest to bring her out. Of course I would have. But I'd have recognized a year, maybe eighteen months or so in that it wasn't going to change, or at least it wasn't going to change with me in the picture, and I'd have pulled myself and my daughter out of that descent into hell. My daughter would've only been 2-2 1/2 then, and I'd have saved her from going through that at the worst possible time (according to the Parental Responsibility Evaluator age 5-7 is the worst time for a child to go through a divorce, psychologically speaking), and just as importantly, I'd have saved myself 3 or so years that I can never get back.
Or at least I'd tell my 20 yr old self to look out for that at age 40 or so....