Why do narcissist move on so easily?

All the sweet, long-term promises were just to keep you quiet. The narcissist had a shallow, specific goal in mind, and it had nothing to do with love or idealization. Those were just illusions.

Narcissists move on so easily because they’ve gotten what they wanted from you. Once they’ve taken what they needed, they look for someone else who can offer something new or better.

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You might have been their practice partner for a skill they wanted to learn, a place to crash while they figured out their next step, or someone attractive to show off in front of their ex. Whatever it was, the ride is over.