I'm not surprised that the literature on narcissism isn't helping you, because looking for books to help overcome your narcissism is the last thing a real narcissist would do. In their world view, the problem is always everyone else. It sounds more like you're growing, and learning something about how your ego operates, which is a good sign.
The question is how to grow further in this direction. In my life, the thing that has helped the most with this so far is the practice of self-observation as taught by certain spiritual traditions. Here's a brief summary: when you observe how you react to things internally, especially if you can observe it neutrally and without judgment, you begin to see a lot about how you've been treating other people and why. The magic is that it then changes on its own, without you having to do anything extra. Self-awareness and self-honesty are the only ingredients you have to add. That's fortunate, because self-honesty is already a lot. We have a strong tendency to lie to ourselves, rationalize, and excuse nearly everything. On the plus side, the more that dissolves, the easier it gets to be with yourself. Self-observation is the solvent.
If this approach interests you, one thing you might take a look at is the books of Vernon Howard. (Don't be put off by their titles. The contents are serious.) If you're sincere about self-work, they provide the clearest explanation that I've run across. Self-observation is, of course, a classical spiritual teaching, but Howard distilled it into modern language in a way that is extremely direct and does not ask you to take on any belief (e.g. any religious belief). The main thing that makes his writing different from so much other self-help material is that he does not flatter or coddle the reader. He gives it to you straight.
I also agree with the commenters who suggest working with a therapist, because the ego behaviors you're asking about are typically rooted in past painful experiences that created a need in us to armor ourselves against future pain. Self-work seems to require journeying back into those realms in order to heal. Then you can let go of your selfish behaviors because you just don't need them anymore, just like you wouldn't wear a heavy suit of armor once you no longer feel it's necessary. What doesn't work, in my experience, is trying to be less selfish only in a rational or ethical way. That approach amounts to imposing a censorship layer on top of what you actually feel, which is a form of self-deception which only puts more weight on you and eventually collapses.
The thing to watch out for in finding a therapist is the personal connection between you and them. The method matters less than the personal connection.
More generally, there are so many good suggestions in this thread that you should probably pick the ones that have the most energy for you and give them a try. Your sincerity is really the thing that will change this for you, so do what feels most inspiring.
I went to my therapist once and said "I have terrible news, according to this book on narcissism, 8 of the 13 symptoms apply. I'm totally one. How can I fix it? Is it fixable?"
And she smiled and said..."a real narcissist would never ask that."
Yeah, but it's not a binary thing, it's a continuum. It's perfectly possible for someone like you, the OP, myself, others reading this to have strong narcissistic tendencies but to be self-aware enough to want to change and not be a complete malignant narcissist, the kind who destroy lives and end up on true crime podcasts.
The question is how to grow further in this direction. In my life, the thing that has helped the most with this so far is the practice of self-observation as taught by certain spiritual traditions. Here's a brief summary: when you observe how you react to things internally, especially if you can observe it neutrally and without judgment, you begin to see a lot about how you've been treating other people and why. The magic is that it then changes on its own, without you having to do anything extra. Self-awareness and self-honesty are the only ingredients you have to add. That's fortunate, because self-honesty is already a lot. We have a strong tendency to lie to ourselves, rationalize, and excuse nearly everything. On the plus side, the more that dissolves, the easier it gets to be with yourself. Self-observation is the solvent.
If this approach interests you, one thing you might take a look at is the books of Vernon Howard. (Don't be put off by their titles. The contents are serious.) If you're sincere about self-work, they provide the clearest explanation that I've run across. Self-observation is, of course, a classical spiritual teaching, but Howard distilled it into modern language in a way that is extremely direct and does not ask you to take on any belief (e.g. any religious belief). The main thing that makes his writing different from so much other self-help material is that he does not flatter or coddle the reader. He gives it to you straight.
I also agree with the commenters who suggest working with a therapist, because the ego behaviors you're asking about are typically rooted in past painful experiences that created a need in us to armor ourselves against future pain. Self-work seems to require journeying back into those realms in order to heal. Then you can let go of your selfish behaviors because you just don't need them anymore, just like you wouldn't wear a heavy suit of armor once you no longer feel it's necessary. What doesn't work, in my experience, is trying to be less selfish only in a rational or ethical way. That approach amounts to imposing a censorship layer on top of what you actually feel, which is a form of self-deception which only puts more weight on you and eventually collapses.
The thing to watch out for in finding a therapist is the personal connection between you and them. The method matters less than the personal connection.
More generally, there are so many good suggestions in this thread that you should probably pick the ones that have the most energy for you and give them a try. Your sincerity is really the thing that will change this for you, so do what feels most inspiring.