I hope OP feels able to come back.
Please end it. Please end it now. He will always love the bottle more than you, more than anyone, more than the entire world put together.
This is not about you being unloveable or anything like that. You sound so caring. This is about him and the love of his life - the alcohol - and he will always put that first, regardless of the effect on you or your children or your relationship with him. The love of his life will destroy you as a person, and lay waste to the happiness of your children, your wider family relationships and your friendships.
He is on the road to nowhere. He will promise to change. He will promise you that every single morning. By evening, he will be drunk again. And you will be sitting there watching your life wither away to nothing.
I am sorry to sound so bleak - this will be hard for you to hear - but I speak from experience.
There is help available for him but the only ones who can do it are professionals. They are accustomed to dealing with repeated failure but they are not emotionally invested so they can cope with it. You can't fix him. If you try, he'll break you in the process.
It has taken much courage for you to write your opening post so please do what your head is already telling you. 💐