Retaliation

When deprived of narcissistic supply, narcissists experience symptoms similar to the withdrawal symptoms of a drug addict; becoming delusional, agitated, helpless, and emotionally unhinged. They disintegrate and crumble, and may even experience a psychotic episode. They engage in “magical thinking;” believing that they are omniscient, omnipotent, and that they cannot fail. This makes them fearless and relentless in their pursuit of revenge.

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See also:
Vindictiveness
Narcissistic Supply (Wikipedia))
Narcissistic Supply (The Narcissistic Life)
Narcissistic Supply (Daughters of Narcissistic Mothers)
Narcissists, Narcissistic Supply and Sources of Supply (Sam Vaknin)

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