Narcissism is a psychological condition in which a person is self-absorbed to the point of mental illness. It is more than just being egocentric (self-centered or selfish); it is a kind of self-love or self-admiration that supersedes all else and determines how all of his life is lived.
Narcissism was identified by Sigmund Freud and refers to a character in Greek mythology. Narcissus was a young man who fell in love with his own image which was reflected in a pool of water. This condition causes serious problems in a person's social interactions, of course, as no one can be as important to him as he is to himself. Sustaining healthy relationships is nearly impossible for a true narcissist, and there is little remorse or regret for hurting or using the people around him, which a narcissist inevitably does.
Narcissistic injury, then, is any perceived threat to a narcissist's self-value or self-worth.
Narcissistic injury (or narcissistic scar) is a phrase used by Sigmund Freud in the 1920s; narcissistic wound and narcissistic blow are further, almost interchangeable terms.
These injuries, according to Freud, are often connected to childhood traumas as he defined them. He mentions things like a young boy who no longer breastfeeds; when he loses access to his mother'd breast, he feels a loss of self-worth. The same result happens, according to Freud, from a child's "daily surrender of his faeces [feces]." Little girls experience narcissistic injuries when they realize they do not have a penis like their male counterparts (a condition known as "penis envy") and her narcissism is scarred because of that "sense of inferiority."
Edmund Bergler expanded Freud's thinking on narcissistic injury, including anything that threatens a baby's (who is naturally narcissistic) omnipotence.
The natural result of a narcissistic injury is narcissistic rage, the "uncontrollable and unexpected" outburst of anger at whatever caused the injury.
The best way to treat a narcissistic injury, according to psychoanalysts, is to have the patient go back and relive the injury so he can deal with it in a more healthy and mature way than he did as a child.
This injury is based on people believing they are not worthy of something or once they suffer that loss, they were never deserving in the first place and this leads to the injury. Some of these injuries can relate to childhood traumas and from that manifest all the way into adulthood.