Rage is very common in people who don’t have a normal, healthy sense of being a distinct, real person. These people desperately, addictively need and compulsively strive toward the Substitute Sense of Self. They have been forced by early circumstances to go for that and when that striving runs into obstacles, so they can’t reach the goal of approval from others or themselves (virtual approval!) they subconsciously feel their life depends on they go into deep frustration that easily culminates in rage. This emotion is based on deep fear. The rage is especially intense when an obstacle thwarts success at the last minute.
This rage is way out of proportion to the ordinary-seeming situation, and often frightens the person and others. It can lead to violence.