ONE LIFE. I also agree with Ezra about this. There is, of course, no "correct" choice for dealing with a such a tragedy, and had Edwards dropped out of the race to take care of his wife it would be entirely beyond criticism. But the same, I think, is true of the choice they did make. As I've said elsewhere, I certainly would not want my hypothetical spouse to give up her lifelong ambition because I got sick. Good luck to them both.
(If there's one thing we know about comment trolls, it's that they're lazy)