Kudos to you Rosenkrantz, absolutely you must "face your own demons" first. and really the first of those is the realization that, on some level, you are being/feeling like you are being abused. It sounds so simple but that part was very difficult for me, especially when my N was so good at convincing me that I wasn't!!
Sjkravill, I don't think that anyone here would "tell" you that you "should" leave your husband. And I understand the part about being overwhelmed with the information and understanding on this board. So many have felt that they were the only ones to live in such craziness. So sad that there are so many of us and so wonderful that there are so many that are becoming aware and taking step to remove themselves from the abuse.
As Rosenkrantz said, "baby steps." Just starting to understand narcissism is extremely painful and disorienting. As for not coming here regularly, we are here when you need us.
To answer your question, it took me a year and a half to actually leave my N, after discovering that he was an N. One day it just became crystal clear and from then on all of my energy was focused on leaving and my recovery. My family and my friends were a great support. After I finally did leave, they confessed that it took everything in them NOT to tell me to GET OUT a long time ago. But they let me discover it in my own time, which is as it should be because then it comes from inside of you.
Also, I needed to get strong enough to actually do it. The things that you are working on, like being aware of boundaries and setting them are wonderful steps. If your husband can change his behavior, that is great. My N's behavior changed somewhat too, but I soon realized that the abuse just became more subtle. He really was a verbal magician. He seemed "nicer" but really he had not changed at all, he was just more careful.
What I found and others have also expressed, is that once you learn about narcissism, you won't unlearn it. Kind of like refolding a brand new map, it's never quite perfectly flat ever again. If he truly is an N, it will keep jumping out at you. I have become very vigilant, probably too much so. But the pendulum will swing back.
So, do whatever is comfortable for you, that's the best way to live life anyway, narcissism or not. And come back and tell us how you are doing evey now and then.