Totally agree with everyone else on this. I completely understand your desire to understand his behaviours (I looked into NPD too) because in some way for me, at least, it was comfort on some level. I spent a lot of wasted energy on that topic and it took me further from what I had to do to JUST scratch the surface on healing from my dysfunctional relationship.
I sent out a link to the break the cycle free course, because to me it looks like a helpful tool to do a self-study and to work towards healing. We didn't cause anyone to use alcohol...but we were in that mix and it hurt and now some of us (me especially) are standing in the abyss wondering...what now, who am I and what do I do now?
I put off this work for MANY YEARS, I am middle age and I want the real me to take charge of my life.
Do what is right for you in this moment, wind down the path and you will find what you are looking for, it is inevitable and it can't be ignored.