Hope this helps someone.
The person with Narcissistic Personality Disorder:
* Lacks the ability to empathize. They can fake it on and off, but if you have enough exposure to the person, eventually you will see this pattern clearly. They may show zero emotion when hearing news of, for example, deep suffering of huge numbers of people.
* Loves attention, even bad attention.
* As psychiatrist Thom Hartmann says, they "Kiss up and Kick Down", meaning they are incapable of having truly healthy relationships. They regard other humans as a kind of resource to be used for their own ends. People they have relationships with become part of their "pyramid marketing scheme downline".
* Goes from incredible highs to deep lows. When they are high, they might not be able to stop talking. When they are low, they struggle to say good morning. (seems bipolar but is not)
* May fly into a rage at the slightest provocation on some days. And at other times, they seem impervious even to the most brutal attack. They might stay awake all night wrestling with a single innocuous thing you said to them the day before, and then launch at you the next day with some bizarre logical conclusion of it.
* When you challenge their behavior, you may quickly move from Friend to Enemy. Sufferers of NPD think in black-and-white terms. You are either "with them or against them".
* Ultimately, they are at the center of the universe. Just like an alcoholic, they will risk a lot to get their next fix.
* Their relationships with newcomers go through three stages that I have identified: (1) Enchantment to (2) Disenchantment to (3) Contempt. [ ] They may go directly to the Contempt stage if the new person show no signs of adoration or reverence early on.
* Often respond in the opposite way to what you might expect. (BACKWARDS reactions - they attack when they should comfort)
* They are attracted to positions of power and particularly those where their decisions are rarely questioned. They regard themselves as "the decider". They often just don't get that others may have a contribution to make to the decision process. You can see that in their language. They talk as if they have the facts. They begin sentences like this "the reality is..." and "the fact is..." and so on.
* NPD starts early and its sufferers have over decades developed an impressive range of dis-empowerment skills, from "you are being too sensitive" to talk about a person being a "good person" or a "bad person".
* They are masters at setting one person against another, and they construct a culture of distrust and hostility.
* They always believe they are right.
From what I have read, NPD sufferers rarely get clinically diagnosed, let alone treated. I can understand that. Just imagine waking up with the notion that you might be afflicted with this condition; you would have to build your life from scratch, even if you did believe treatment were possible - which it's not.
There are plenty of people out there who have suffered at the hands of a Narcissist, and extensive research has been done to help you identify it. The Internet is awash with anecdotes, life stories, and the results of research.
The best thing you can do to protect yourself from a Narcissist is to stay away from them. Give it time and Narcissistic Personality Disorder, if you are exposed to it in someone in whom you have personally invested, will hurt you. I guarantee it. It's a slow nibbling-to-death process.
First, you're attracted to this striking person because you seem to have so much in common with them, and striking they are, as they weave a web around you. They know exactly how to get attention - they've been perfecting the art since childhood. What's really happening is you are being prepared for dinner. Their dinner. And you are but one of their side-dishes. They don't count how many little folks like you they have consumed over the years.
A spider doesn't count the flies he eats and he has no feelings for any of them. The fly is just dinner; that's the fly's place in this world. When you have a relationship with someone under the influence of NPD, you are the fly.