According to Sam Vaknin, self-proclaimed narcissist and author of Malignant Self-Love, the simplest way is by abandoning him or by threatening to abandon him. The threat to abandon can be vague and doesn’t have to be conditional (“If you do/ don’t do something – I will leave you”). When you confront a narcissist, you must be insistent and shout back. He or she can be controlled by the exact weapons that he uses to overpower others.
Their fear of abandonment overshadows almost everything else in a narcissist’s life. For example, if he gets emotionally close to someone he begins to fear that abandonment is inevitable. That causes him to act cruel and distance himself which often results in the abandonment that he feared. It is the narcissist’s paradox to which also holds the key to confronting and coping with the narcissist. If he engages in narcissistic rage – rage back at him. This inflames the fear of being abandoned and consequently quiets and calms him. He will try to make amends, immediately moving from one end of the emotional spectrum (cold, angry, cynical, and cruel) to the other end of the spectrum (warm, loving, optimistic and kind).
Mirror the narcissist’s actions and repeat his words back to him: If he threatens you – threaten him back. If he leaves the house – you leave the house. If he acts suspicious – you act suspicious. Descend to his level and use criticism, degrading comments and humiliation. Mirror his image back to him and the narcissist will always retreat.
https://thenarcissisticlife.com/confronting-a-narcissist-with-his-own-behavior-what-will-happen/
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