"The moment you begin resenting a person, you become his slave. He controls your dreams, absorbs your digestion, robs you of your peace of mind and good will, and takes away the pleasure of your work. He ruins your religion and nullifies your freedom of mind and hounds you wherever you go.
There is no way to escape the person you resent. He is with you when you are awake; he invades your privacy when you sleep. He is close beside you when you eat, when you drive your car and when you are on the job.
You can never have efficiency nor happiness. He influences even the tone of your voice. He requires you to take medicine for indigestion, headaches and loss of energy. He even steals your last moment of consciousness before you go to sleep.
So if you want to be a slave, harbor your resentment."
- author unknown