GG - it is hard when we see a big change in a parent. My dad died from/with Alzheimers which overwhelmed him.
I am coming to the view, working with a very gifted therapist on a project, that much depression comes from our most basic fears (these will be different for each person) I can also see that mindfulness, the practice of living in the moment, is a powerful tool for the depressed person to self help with.
Why did your mother need to be super woman in the first place? What was she compensating for, or to put it another way, what fear was driving her? Self acceptance is a huge need throughout life, but especially as we get older and cannot do all of the things we used to do. Add in superwoman and yes, you have a recipe for what looks like a crisis.
Our whole life is really a process of becoming - some call it a journey, and it is never too late to learn more about ourselves