No one will see this except for you. Try re-creating those difficult moments in your life as if you were writing a story or a play. See what words, images or themes continually crop up. Or just do free association as you think about a painful incident. Write whatever comes to mind.
Anger is a natural response to many frustrations in life.
Subsequently, the rage we feel remains inside of us. A liberating release is to pile a lot of pillows in the middle of the floor once or twice a week and just whack away. You may be surprised at the enthusiasm to which you take to this. The point is to release everything you've wanted to say. Breathe slowly and calmly as you imagine yourself in the scene again.