You are right. No one causes someone to commit suicide (or murder their children), it's an internal problem in that person. You cannot force a mentally ill person to become better, you cannot force an alcoholic to stop drinking or a drug abuser to stop drugs. No one really has that kind of control over another person's will.
He could have (should have) had her committed to the state hospital until stabilized, or at least made sure someone else was always with her and the children - not depending solely on his mother.
Fitz, I love ya, and usually you do such a good job saying what I think, I don't bother to post. : ) But I can't go with you on this one. I agree that she deserves whatever she has coming, maybe more, but I can't picture you as the type to make excuses for this bozo.
Nor can I picture you as the type to let your children live in squalor just because you have a principle that, because it is the woman's job, if she can't/wont provide a healthy home, they'll just have to grin & bear it. That is typical Illbay, but you???
I keep wondering what personal experience you endured to get you off-track on this one. ; )