BUT lo, there is a critical mass of character pain, after which you, dear author, will begin to look more and more like a sadistic bastard and the novel will become less and less enjoyable. You are drowning your plants in fertilizer.
I think that Stephen King is a good author-ly voice to heed. He certainly knows how it’s done–he can buy all the groceries he wants, now! In fact, I think he’s hit the nail on the head. The nail is the problem, of course. And King might have been defining success, but I believe he’s actually defining the issue many aspiring “writers” face: bein’ considered legit. Street credit, if you follow.