Salon says:

“Weeds” TV show and “Red” movie actress Mary-Louise Parker is quitting acting because the world “has gotten too mean for me,” she told News Corp Australia. “It’s just too bitchy.”

Calling herself “thin-skinned,” Parker referred to Internet blogs and reality TV as perpetuators of negativity and criticism, “and there’s more of that than there is whatever praise people think you’re getting,” she said.

It's a well-known fact that you have to read three million compliments on the internet to make up for one negative comment.