I have dealt with many people with PD, all through my life, inside and outside family. It took me a while to understand and I have tried to learn about it to defend myself against it, since you tend to connect with people that have the energy that is familiar to you.

Rewire the brain and the emotional body takes time, and this people take a snapshot of you at first sight and they know which buttons to press.

It's fascinating.

Some are aware, others are not. Psychopaths are damn aware of what they are doing. 
Narcissist I don't think so, is a mechanics of self defense. Of course if NPD his pared with another cluster B, they can be somehow aware. At least they have the perception that things don't go well to them. That's why one of their most common frases are "How dare you ?" And the face expression let you know that they are shocked in disbelief. It's not fake