Facing Critics and Naysayers

I was trying to encourage a fellow writer today who was feeling down because of mean-spirited Amazon customer reviewers. We've all read a few doozies that made us shake our heads, haven't we?   The struggle is not unique to writers, as Stephen King states.  It applies to just about anything you do publicly, or that becomes public knowledge.  We will always have detractors, critics, and naysayers.   It's a sign that you're doing something that matters.

Anyway, I came upon some sage advice from some fairly well-known writers on the topic:

“I have spent a good many years since--too many, I think--being ashamed about what I write. I think I was forty before I realized that almost every writer of fiction or poetry who has ever published a line has been accused by someone of wasting his or her God-given talent. If you write (or paint or dance or sculpt or sing, I suppose), someone will try to make you feel lousy about it, that's all.” ― Stephen King, On Writing

“Some people insist that 'mediocre' is better than 'best.' They delight in clipping wings because they themselves can't fly. They despise brains because they have none.”
― Robert A. Heinlein, Have Space Suit—Will Travel

“Critics are to authors what dogs are to lamp-posts.”
― Jeffrey Robinson

“When you're different, sometimes you don't see the millions of people who accept you for what you are. All you notice is the person who doesn't.”
― Jodi Picoult, Change of Heart

What kind of critics, detractors and naysayers have you faced?  How did you deal with it?  I'd love to know.  Please discuss in the comments section below.