Earlier quoted context omitted.
Your stepfather apparently violated your mother's directive based on the desperate belief that his spouse could recover, and she did not. This is absolutely tragic. Then your stepfather presumably refused kill his spouse (due to hope, moral beliefs, cowardice, etc.) by unplugging her from standard, non-extraordinary life-support. She eventually died a painless death. For which of these does he deserve to suffer for,…
> I also absolutely do not want anyone to euthanize me if I somehow end up semi-vegetative. Just out of curiosity, why not?
Technically it's the same reason that I don't want someone to euthanize me right now. The value of my life does not derive from feeling happy or otherwise using my senses. Nothing important changes when I have brain damage (or cancer, or depression). All I have to do is be human, and my life has a certain type of value that makes it wrong for anyone to intentionally end it.
If I try to build in loopholes, or start messing with semantics, or if I compromise because something is going to hurt, I end up being unable to act from reasoned moral principles, which is something else I value.
(I have a similar curiosity, if you'd oblige, about what makes euthanasia any different from simple suicide - I actually asked that earlier, but all I got was downvotes.)