He was staying with her but he moved out. He was trying to get into an addiction treatment program, but had trouble staying sober.
Of course, it's possible that she could have taken him directly to such a program somewhere.
In retrospect that would have been the right choice, but it could be that things just broke in the wrong way, that she assumed he was working things out when he wasn't..
I guess she should have paid a Hooker to take care of Dear Old Dad.