B,
I am so sorry for your pain. Hon, I waited 34 years and finally "figured" out that he wasn't going to get help. I could no longer live with it also. You are not alone. No one says that after you leave that you can't get back together. No one says that you don't love your husband. We all love our addicts, but it doesn't mean that we have to live in the circus with them.
He might just realize that you mean business, by moving out. You probably have threatened so many times that he doesn't believe you anymore about leaving. I am sure he will be surprised.
I want to tell you the best thing I did for me and my kids was divorce my ah. I look back at what he did to me for years and years and what I tolerated from him. I can't even believe it was me. I am happy, I smile every day, my kids are happy. Life is so calm and quiet, I have money to spend on me. I stopped obsessing about AXH who he was with, what he was doing, the money he was spending and so on. Alcoholics are truly exhausting.
Keep moving forward, 15 years is a very long time living with an addict. You and your family will be ok, deep breaths and pray that he sees the lite and seeks sobriety.