This idea that a writer's characters are them, or their friends, or their children is one that vaguely disturbs me because I don't see it as healthy. If somebody doesn't like a writer's characters, then, on some level, it would mean they don't like the writer. Or at least parts of them. How can anybody with even the best self-esteem deal with negative reviews and rejections when they're rejections of YOU?
For any artist, there needs to be some level of disconnect between them and their work if they want to last for any length of time with their sanity intact. How can you add the necessary amount of danger and terror by killing/maiming characters if they're your friends/children?
My characters are not my friends, my children nor are they me. They are my characters. They are simply ideas I've thought up and given written form to. Whatever part of me might find its way into them is so minute and removed from me that it makes no difference.
I'm not going to spare them from pain, death, or torture. When somebody says something negative about them, I don't take it as a slam against me. A slam against my writing ability maybe, but not me as a person.