Her demise is self inflicted and she has had far more chances at redemption than most people. She has (literally on occasion) stuck up 2 fingers at everyone regardless of what she's done, what she owes, what's she's responsible for etc.
She only jumped on the MH bandwagon to get away with her behaviour. If she loved anyone besides herself, she would have fought tooth and nail to see her children.
As for her mother, she milked the story as much as she could. As sad as it is for AP to have this disease, I don't think it bothers KP as much as she made out. The main reason being, that she refused to change her behaviour, refused to give up drink and drugs or do anything to give her that "reassurance" she went on about. She said she wanted to rush getting married so AP could be there. Any decent person would have fixed up their act instead.
Each chance she got, she chose to fly abroad with Cole instead of spending these precious moments with her mother.
The only sad part of this whole this is not her self inflicted demise, but the people she has hurt.