I had a relationship with someone who also drank alcoholically in my early-mid-30's. For years, I regarded him the love of my life (and vice versa). It was first one of those encounters with instant intense chemistry, then turned completely obsessive, just as addictive as the alcohol we drank itself. I gave up all my carefully designed, positive long-term plans to stay with him... sort of unlike me as I never did anything similar before/after for anyone. During the initial years, we both were in deep denial about the addiction problems and instead, engaged in a fantasy world, stopped participating in normal life in many ways, and kept cultivating ideas, feelings and imaginations that became increasingly detached from reality, hanging onto each-other and our destructive mental worlds as though everything else was unnecessary and uninteresting. We both managed to retain some level of "normal life" functioning (eg. jobs) but clearly everything was headed south, while still clinging to the perception that we were tied in some sort of incredible, transcendental love together. It was me who "woke up" from it first, after those dreams we had created together did not go anywhere for years and it became frustrating and hopeless. I recognized that a lot of it was because of the drinking and suggested to him that we somehow seek help and get sober together. Did not work. Eventually, I took a leap and gave up on it, moved jobs, location, and set up a very different life. But still could not detach from my BF... we kept "relapsing" with the relationship, now long distance, for a couple more years. I also never got sober while in it.
Eventually I cut every contact with him, which was hard because he did not just accept it at start. It broke my heart because I still loved him very much and it was awful to cut the ties completely and definitively. It took me some more time to get into recovery and my life has changed very dramatically since. Part of it is that in sobriety, I started a new relationship with someone local, someone who did not feel like some kind of "spiritual connection", but turned out a much much better fit with me in every possible way. It is not based on my relentless seeking (and projecting) familiarity and similarity onto select others like was the pattern of my youth, but a scenario where our traits, preferences and interests complement well.
I just ran into my ex accidentally a couple weeks ago, after years. It wasn't a pleasant encounter... he still drinks and did not look very good at all. Yet, of course it triggered a lot of feelings... What I can say without doubt, is that it is one of the best choices I have ever made, to get away from him and from that environment. I could not have imagined for quite a while that I would have a healthy, loving relationship that does not involve craziness and destruction after him... but I am in it now. No obsession, no extremes. I've learned from this experience that love does not have to be craziness and can be a relaxing, life enhancing experience. The ex was extremely hard to let go of, but I am nothing but grateful about the choice and the eventual outcome.
It took me a few years to get over the ex completely and for a good while, I found myself projecting my memories about him/us onto others, looking for "him" everywhere. It took a good deal of self awareness and work to get over this pattern but I feel I am free of it now and with it, came a lot of mental peace and liberation.