I can think of a number of medical issues I wouldn't want to live through but then again, would I have the courage to actually end my life? Wouldn't be an easy thing to do for most people.

Two things-

My older sister got cancer and somehow two of her vertebra went bad after the operation and radiation and chemo. She became incontinent and had mobility issues. Fast forward and she's estranged from her adapted daughter, living alone and she's very large, bedridden, and her feet don't angle up and are flat in the bed. She comments on FB that she really doesn't like living alone and has to have a woman come in every day to feed and clean her. But she could drink wine and watch TV. She died about 6 weeks after saying she didn't like living alone. We may have some self regulating mechanisms we don't know about. Contrast that with my wife's grandma who turned 106 and everyone loves her. Still gets around.

I remember a Jack London story of an old man that was left behind by the moving tribe in the cold snow, because they couldn't take care of him anymore. He was a burden. He waited silently and the story ends with the wolves closing in. I'm glad we don't do that.