Sometimes we twist it out of habit, sometimes because the real cause of the anger cannot recognize, she sits deep inside and pushes at the thought of universal injustice, for example. And they have already provoked anger.
Still it happens that a demonstration of anger people sought from surrounding what he wanted. Remember the cute girl that such terrible eyes could make that huge men aghast agree to all its proposals. She didn't realize that so manipulated by others, and then wondered why it closed even close.
Ekman even wrote that if a person frequently and for extended periods of time experiencing anger in varying degrees (from slight irritation to rage) formed such a trait-hostility. As would say my university lecturer of psychophysiology, "Spiteful girl will never become a good grandmother." Keep in mind!
It is important to learn to notice the thought provoking anger, to investigate the circumstances in which they appear, and what feelings they provoke. Not an easy job. You should start with meditation. Come and work with the psychologist is able to significantly speed up the process.