I think the key to Coulter is to see her as a 13 year-old child, acting out.
On the talk shows, where she has to interact with sensible humans, you'll notice that immediately after she utters one of her outrageous statements, you'll see there is a blank look of expectation on her face. "There! I just said that! What are you going to do about it, Mommy?"
What's sad is not her per se, but the fact that in our society this person can make a career out of this, that people hire her to do this.