Koran, I agree with SG, you are very self aware and it will stand you in good stead over the coming festivities.
I too felt an amount of responsibility towards my first husbands drinking. I was very codependent, and completely enabled him. I felt huge guilt initially when I ended things, but I felt I had given him every opportunity to make things right. And as you say, when one person is working at putting things right, the other not so much? A relationship is really up against it. My 1st hubby was a bit like you, initiating the drinking. After time it became "well if you can't beat them join them" but after 12 years that got old. I wanted to 'grow up' do things with what was left of my life. He didn't. I had helped absolve him of all responsibilities for so long that when I told him enough was enough he was a little boy lost. I couldn't go back to him though, it would certainly have killed me. In the end, it did kill him. It was later and into my second marriage when drink really took over my life. Fortunately for me, I have a wonderful man who had stood by my full disclosure, and supported my sobriety. He is proud of my achievements.
At the time of ending my first marriage I wondered at a future. Now I have a bright shiny present that suits me just fine.