anger is inside you.
Anger is not caused by an insult, does not arise as a result of an insult. If you did not have the energy of anger within you, the insult would remain powerless.
It would just pass by without bothering you. There are no causes outside human consciousness; reasons exist only within you. You are the cause of everything in your life, and to understand this is to understand one of the most fundamental truths.
To understand this is to begin the journey of transformation.