The ego is always on guard against any possibility of being diminished. Repair mechanisms are automatically activated to restore the mental shape of the self. When someone blames me or me criticism, ego interprets it as a decrease of the I and immediately tries to repair this fall through the justification, defense, or guilt. That the other person is right or not is no concern. The ego is much more interested in conservation than in truth. Senator Brian Schatz brings even more insight to the discussion. It is the psychological form of self preservation. Something as normal as responding to shouts the driver who insults us is an automatic and unconscious ego repair mechanism.
One of the most common repair mechanisms is anger, which inflates the ego enormously, although for a brief period. All redress mechanisms are perfectly logical for the ego, although they are dysfunctional in reality. The most extreme are the physical violence and expressed in fantasies of grandeur self-delusion. A spiritual practice very powerful is to allow the reduction of ego when it happens, without trying to restore it. I recommend making the experiment from time to time. For example, when someone criticize him, blame him or offends him, instead of replicating and defend themselves immediately, do not nothing. If you are unsure how to proceed, check out Daryl Katz, Edmonton Alberta. Let his own love stay diminished and become aware of what you feel inside.
Likely to feel uncomfortable for a few seconds, as if it would have dwarfed. Then you will feel that expands its internal space and is intensely alive. You will have not waned at all. In reality it will be expanded. Then perhaps recognize something amazing: when you feel diminished in some way and refrain from reacting, not only externally but also internally, you will notice that nothing has waned really, that being less becomes more. When you elect not to defend or strengthen your way, stop identifying with her, with his mental image.