Narcissists are brain damaged, incomplete beings; they don’t know any other way to behave, and they are generally* not capable of learning new ways to behave. In the same way a shark must keep swimming or die, the narcissist goes through the same motions of idealize, devalue, discard with each new source of supply. As someone else put it, it’s the same as reaching for a glass of water when you’re thirsty. It is a very automatic and non-conscious behavior pattern.
Also, due to their cognitive deformity, the things that make normal people comfortable and happy make the narcissist uncomfortable and unhappy, while things that normal people find exhausting and miserable are energizing to the narcissist. A calm day at home with loved ones, for example, sounds heavenly to most people, but a narcissist would be very bored and unhappy in that situation and force a conflict or disagreement to feed their need for drama and nonsense. Another example of their backwards wiring is to observe a narcissist in an argument. They will push and fuss, attack and argue with their target until the target finally explodes in tears or anger. Once they have goaded their target into an outburst, they become calm and happy. It is exactly backwards of a normal person’s emotional response.
Unfortunately the disorder does not allow them to become conscious and without being aware that they are repeating a pattern of dysfunction with each new person they bring into their life, they do not have the ability to self-reflect and change.
*I am speaking in broad absolutes. It may be possible for a narcissist to change their behavior, but it would be very difficult and would require a great deal of professional help and a lot of personal effort from the narcissist. If a person is getting what they want, they don’t have much motivation to change.
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