" Physical symptoms such as muscle tension, back problems, stomach distress, constipation, diarrhea, headaches, obesity or maybe even hypertension can be caused by suppressing your emotions. Suppressed anger may also cause you to overreact to people and situations or to act inappropriately. Unexpressed anger can cause you to become irritable, irrational, and prone to emotional outbursts and episodes of depression. "

― Beverly Engel , The Nice Girl Syndrome: Stop Being Manipulated and Abused -- And Start Standing Up for Yourself