Love, to a narcissist, means he gets supply in the form of admiration and worship, has a feeling of power over you, and can manipulate and use you to their own ends, and that you reflect well on him to others.
In the world of the narcissist, "truth", from the N, means lying. "Honesty" means manipulation and deception. The N's future triumphs mean "day dreams about success" and delusions of grandeur. Trust, from you, means blindly ignoring signs of cheating. You get the idea.
My point is that if I use the word "chair" and actually mean "car", and carry that out to it's fullest, there will be constant confusion in the hearer, YOU. This post is the clue you need to understand why you are confused about the narcissist's behavior....it doesn't match the words. If the narcissist actually used the words as the N secretly defines them, your eyes would be opened immediately.
As it is, if you keep trying to understand the N by thinking that the N and you are using vocabulary with the same meaning, the N becomes incomprehensible. If you, instead, DETACH AND OBSERVE the narcissist, and, seeing what he does, assign the word to that behavior that makes the most amount of sense, now it makes sense.
In short, you have to ignore what the N says, and watch what the N does, and say IN PLAIN STREET LANGUAGE what that is. If the N is abusive, say so to yourself. If the N is a lying cheater, say so. If the N is selfish, say so.
You may have watched the Antiques Roadshow. On that show, people often come in with an item they bought that came with a story, but the story is totally wrong, probably told to induce them to buy it. When I used to deal in antiques, I had a rule: buy the item, not the story, no matter who is telling it. It was a lesson I learned the hard way. I suggest you remember this rule and do likewise.