I'm sorry, babe. I'm an old fart now but when I was in my teens, I dated this amazing guy. He told me I was the love of his and that he wanted to spend the rest of his life with me. That nobody understood him like I did. That he was terrified that I would leave him because I meant everything to him. And then I found injection needles in his bathroom. And I knew he wasn't a diabetic.
I gave him an ultimatum: Me or the drugs. Never for a second did I think he would actually choose the drugs. After all he had said. But he did. He chose the drugs over me.
I was heartbroken. I couldn't understand how the drugs could mean more to him than our love. Than me. Than what we had together.
I honestly didn't understand until I got out of a marriage to an alcoholic some 30 years later. It's like... addicts have a choice but they don't. It's not an even choice. It's not like they can look rationally at "on the one hand here, I have this amazing relationship with a woman who adores me -- and on the other hand, I have this substance that will first take my money, then my integrity, then my life. Now let's see which one I should choose..." Rationally, it's a no-brainer. But there's no rationality to how an addict thinks about his drug of choice.
I'm sorry you're hurting. Please remember that the fact that he isn't able to see that he has a problem says NOTHING about you. It doesn't rob you of a single ounce of your worth and value.
Take good care of yourself.
Oh -- and one more thing: Don't be surprised if he contacts you again, tells you that he loves you and can't imagine life without you, and that he wants to marry you but you can't talk about his drinking. I've heard that one before.