The power of faith (not necessarily in a Higher Power - self-healing meditation etc can work just as well!) can produce apparent miracles. I had a friend with a husband given 2 weeks at most. She had been involved in the Bristol Group and decided to put him on a vegan diet, perform meditations with him, get hands-on healing for him etc. He lived for 2 more years. When your time comes, you know it and are ready to go, but it's quality, not quantity that is important. If I get dementia, like my mum, or if I can't enjoy walking, nature, music, reading etc., that's when I would wish to be allowed to go with dignity.