Hi, Lost, and welcome to SR. There is a lot of hard-earned wisdom here, and it sounds like you've availed yourself of some of it already by reading the posts. Good for you for reaching out for information and support; you're going to need both, I suspect.
You speak of your A as if he is 2 different people, one when he's drunk and a different one when he's sober, and you're not alone in thinking that way; many of us did. There are 2 things to know about with regards to this: First, it really is all one guy, and he is who he is. Second, as time goes on and the disease progresses (and it will, it's the nature of things), the sober times will become fewer and farther between, until eventually alcoholism and addiction has consumed the man you used to know. It's sad and hard to hear, but it is the truth.
I think the suggestion for Alanon for you is a good one. I'd also recommend that you keep on reading the posts here, making sure not to miss the stickies at the top of the page. There's a lot of useful info there, and knowledge about alcoholism will help you make decisions in the future.
Yes, A's can enter recovery, but as others said, not until they are ready, and your guy does NOT sound like he's ready....why take a front-row seat to the disasters and heartache when there is nothing you can do for him? It would be wiser to take care of yourself and your kid(s) for now.
You've gotten some solid advice here, and I hope you can let it sink in. Wishing you strength and clarity.