Sorry you're going though this. It is tough question you're asking in regard to when it is time to end. I guess the simple answer is when you're ready. But you can get yourself ready, by working on yourself and educating yourself more on alcoholims. This is a great place to help you with that.
In regard to trust, I think it could and should be restored but only if she proves herself to be trustworthy. And when and if that happens you'll know, there is no mistake about it. I don't know if I can ever explain it, but there is something about As who become serious about their recovery that you can spot from milles away, it is so different from all the previous promises.
In regard to your kids, I agree with what others have said. Kids needs to be around functional parents, preferably two, but even one would do better alone than having the other one cought up in madness of alcoholism. Aslo, NA is always affected by the behaviour of an A, and kids always sense that heartache and suffer from it. And this I know for the fact as I am an ACOA (adult child of alcoholic). My AF was never abusive, acctually he had nice personality even when drinking, but still I was deeply affected by it. I resented him for not being "normal" and all the things he missed out in my life. I felt protective of my mum, whose hidden suffering I could sense, while she was trying to put on a happy face as to protect us kids. Kids know so much more than we give them credit for.
In family life during childhood we learn the patterns how to deal with life, what is normal, what is acceptable. Children who grew up in alcoholic households are very confused about all that. They have to guess what is normal. Statistics show they often end up becoming A themselves or marring one. I married one. I always swore I'd never have anything to do with another A in my life, and than I married one. Smart people say the reason for that is the fact that growing up in my family I have learned this kind of life, as confusing and unplesant as it was, still it was something I knew, something that felt normal, that on some subconcious level I knew I was equiped to deal with it and thus I was drown to it.
My husband is in recovery now, only now as my kids are starting to relax and learn other healthy ways of life, I can see the damage that was done to them by my choice to stay in marriage.
Also kids are tought by example, if you were to leave your wife you are taching them her bahaviour is not acceptable, and no one should suffer because of someone else's choices.
I write so much about this as I know how hard it is to make this kind of decision, as I struggled too for a long time trying to figure out what is best thing to do in regard to my kids (ironic, I know, with all past experience as ACOA I should have known better but I didn't). I took me some serious work on myself to come to the right decision. For me it was to leave my husband and talk openly about the whole thing to my kids. They're 12 and 7, but they understood it and took it so well.The reason for that is that by being honest with them I gave them the validation of their reality, something I never got as a child. By having thier reality validated and facts about alcoholism explained, my kids were not as confused any more. everything they went though started making sense to them. things were labeled and thus became possible for them to process them.
As you gathered my husband is RAH now, and is living back with me and kids. We're all learning about normal, and that is a slow but for the most part pleasant process. But also, if he is to decide to start drinking again, he will no longer be staying with us. No way I'd ever again expose my kids and myself to the behaviour of an active A, as simply that is not helping anyone, not even the A, quite the oposite acctually. As should learn to deal with consequneces of their actions. But that's another subject (kind of), and my post is already too long.
take care