I left an addicted spouse. If you go over my past posts, you will piece together the long, sordid story. I don't have an "origin story" post because I was, at the time, being stalked. I am still being harassed in small, upsetting ways, but I'm less scared of the outcome now. It has taken time.
I can tell you that by the time I had to end things, I did so only because I HAD to. I didn't want to. I HAD TO. I loved my exAH. I still do. Of course my exAH is "dead" because he lied to me so much, but the time the mask fell off his face and I realized that underneath it was an evil doppelganger that I never knew I had been living with, it was like the man I fell in love with was dead (not literally). I don't know who he is today... I just know that he was someone who was willing to throw me under the bus when it came to "saving" himself or preserving his ability to use. In retrospect, I was in love with an idea that he helped me cultivate. It was flattering to him for me to look at him in the way that I did, so of course, because he was selfish, he allowed me to keep seeing him that way. I don't know if this is who he intended to become. I don't think he knows it himself -- his problem is control, lack of control over drugs, and the obsessive need to control his intimate partner because he had little control over anything else in his life.
I think you can love someone from a distance. Or you can love the idea of them. But the reality of them is... sobering.
I am free now. Sometimes it scares me. Sometimes I feel terribly lonely. But I am happier now than I was when I was crying in the shower every night and married. I do cry sometimes now... but not because I want him back. I cry because I had wasted so much time with him and I have so little time left... and because I wish I had not spilled the milk.
So... I am not sure if that helps you, that's my story.