Whichever way things go, take care of yourself and your family first.

My father is now in palliative care on the other side of the world with @galenkp handling it all, which is definitely not pleasant and made worse as my father's Alzheimer's is so bad, he doesn't recognize anyone - we lost our mother in 2004 to cancer. Getting old sucks ass - but it sounds like your mother has had the kind of impact on the world that there are people who care deeply for her - that is a good way to have lived.

The best of who we are is often born from the worst of our experience.