The first step is to learn about this condition, and realistically accept the low odds of anything changing, then you can determine how you really feel about the situation you are in. You can read books about it, but a fast free solution that will present the stark reality is to go to Al Anon where you will meet everyone else there who is suffering from an alcoholic relationship. Then you will see that most of the newcomers are in denial saying if only he would change we could have a good life, even though there has never been a good life to base that hope on.
Lots of people get caught up in the drama of caring for an alcoholic because their strong need for drink is the center of their universe and they require so much attention and cause so much disruption in the process of drinking, that the other person often doesn't have time to consider if they want to be with or if they even like the alky. If the alky happens to go dry at some point in their life (small odds of that happening btw) the other person in some cases may realize they were never interested in them but didn't realize it because dealing with the problems the alky creates is so time consuming.