What motivates a narcissist to keep punishing someone endlessly after being called out for their abuse?

Why do narcissists seem to panic when you stop communicating with them, and what does that reveal about their mindset?
What's the best way to handle a narcissist who won't take no for an answer, especially when it comes to shared responsibilities like pets?
Why do narcissists see those who stand up to them as enemies, and how does that affect their behavior?