Gently, tell her what you've told us. My sense of this woman from your description is that she is an emotionally battered woman. She has little sense of self left (if any). I'm sorry but I've heard that thing about keeping a family in tact before. It's often a lie that emotionally butchered and beat-up women tell themselves. She needs more help than Alanon can provide. She's been going for 24 years?
She needs to get in contact with a center for domestic violence. They also deal with emotional abuse.
I volunteer at such a center. And, after listening to the stories of other women there, I feel like I'm whining when I share my issues.