It's interesting to consider (as one gets older and older). Do you want unlimited life support because your loved ones can't deal with death? I'm just seeing the comments below and they are interesting and thoughtful. I'll check the Radiolab episode. Thx.
I can speak from experience, sadly. Someone in my family was diagnosed with a brain tumor the size of a golf ball. She spent a week in the hostpital for tests and the rest of her days at home with family. The nurses that came by basically increased her morphine dosis whenever she felt pain. When her consciousness was too far removed from reality they gave her one last overdosis (note: it's legal here). I'm really glad for the time I had then, but I'm even more glad that she didn't need to suffer any longer. I, too, would prefer a peaceful death as soon as my chances of survival are slim.