I’m sorry to hear about that; it is really a heart-breaking thing to hear; to be facing divorce is a kind of pain that strikes deep. I’m so sorry for that 
A marriage is like building a boat together: the better you both build it and the more regularly you both maintain it (together - the work is always shared work; marriage building and maintenance can’t be done solo), the longer it lasts and the stronger it is. And with a strong, well-maintained boat, you can travel anywhere, to any harbour; and you can withstand any storm in any sea.
Maintaining a marriage can take a lot of different forms but for me and my wife (17 years, including working through some very rough spots), it has involved regular counselling (sometimes yearly, sometimes monthly, and in a few cases every two weeks; we still see a counsellor for ongoing communication coaching). We are also actively involved in our community. We take time every day to check in emotionally: what was hard today? What are you grateful for today? And we listen non-judgmentally.
In your case one important thing to remember is the only choices that belong to you are your choices: you choose to stay sober and clear so you can be present for yourself (to stay healthy and working your recovery), and also for your kids. You may also choose to get some individual communication coaching - visit a relationship counsellor and ask to learn how to communicate and listen; or you can learn to communicate in many free recovery group programs (Resources for our recovery) - then begin some conversations with your wife while you listen with acceptance and empathy, and without judgment. All those things are choices you can make now, and they are all things that will have a constructive impact. What will happen next is not clear but the fact that you will choose healthy, helpful choices is clear.
Don’t give up. You are not defined by your marriage, though it is a big part of your life; you are defined by your choices. You can choose to learn how to be the person you want to be (those recovery groups are helpful with that).