Anger and pain are two seperate things. Born of fear perhaps, but totally different beasts.
Hurting, as with a wound, may heal. It is pain and may also cause anger and outlash before it scars.
But anger comes from inside, and doesn’t heal with time. Anger, like a bomb, needs to be diffused by a professional, taken apart bit by bit to see its components before it explodes and maims all surrounding it.