Resentment is the emotion that goes with complaining and the mental labeling of people and adds even more energy to the ego. Resentment means to feel bitter, indignant, aggrieved, or offended. You resent other people's greed, their dishonesty, their lack of integrity, what they are doing, what they did in the past, what they said, what they failed to do, what they should or shouldn't have done. The ego loves it. Instead of overlooking unconsciousness in others, you make it into their identity. Who is doing that? The unconsciousness in you, the ego. Sometimes the "fault" that you perceive in another isn't even there. It is a total misinterpretation, a projection by a mind conditioned to see enemies and to make itself right or superior. At other times, the fault may be there, but by focusing on it, sometimes to the exclusion of everything else, you amplify it. And what you react to in another, you strengthen in yourself.
— Eckhart Tolle