your presence in his life is not stopping him from drinking.
He's not yours to worry about - and to be miserable for. he is a sentient being who has chosen to drink. He continues to make that choice.
When we are in these relationships, it seems like there could be no other. that things would be perfect if our partner would just stop drinking. But this isn't the case. Our partners are far from perfect. We fear that we are not deserving of a loving, stable, attractive partner. And we keep ourselves in these terrible, sick relationships. We rationalize it, we don't face the self doubt, the shame, the terrible self esteem in a direct manner. We focus on the problems of our sick partner. At least, this is the experience I had. I let it drag me down for far too long, and I wish I had the courage to reach out on a forum like this when I was in a similar situation.
I had a romanticized, unrealistic expectation, version of the girl I was dating in my mind. When spiderqueen mentions grieving, I understand it. We grieve for the person we loved - a person who might have existed only in our minds. the girl from the first few months ceased to exist two years into dating. We had stopped dating long before the "relationship" ended.