He even erased all the things about me that are me
This is a very astute observation and worth more in-depth exploration, but I believe you may have the formula backwards. I know I did. I have a tendency to partake in obsessive/compulsive behaviors. I always have. I am a compulsive overeater, I am compulsively neat, I was compulsively obsessed with my ex boyfriend's behavior and drinking, and more.
I've learned that my obsessions are a way that I abandon myself--not the other way around. I used my obsessions to erase all the things about me that were me. I used them to disappear, to avoid being fully present in my life.
My boyfriend and his drinking didn't erase me; I erased myself. Imagine living for 50 years in the background of compulsions, using my obsessions to avoid living my life.
That's no way to live. My obsessions started out as self-protective behaviors meant to shield me from harm, but over the years as they grew in intensity and frequency and as I nearly ceased to exist, they became the biggest obstacle in my life.
My boyfriend, his drinking, his behaviors--they weren't enemy. The enemy was me. Finding the key to my self-created prison was the first step in living a happy life. You hold the key to happiness in your hands. Your boyfriend does not.