I'm struggling with this as well. My AH was arrested for DWI last week, which brought this all to a head. He told our 8-year-old son the truth - we had talked about it and I knew his arrest would be public record and I didn't want him to hear about it from someone at school, or on his baseball team.
I've told our son that I'm not sure what's going to happen. AH is not drinking now and has had no problems stopping, but he's stopped before. I told DS that his father has a problem with alcohol and that if AH decided to go back to drinking he will have to leave the home because I don't think it's a good environment. It's hard because AH is vey high-functioning, works every day, does lots of stuff around the house...DS has probably seen him drunk twice - after AH's brother died and at his 50th birthday party. I feel the separation/divorce would be more for me, because I can't deal with seeing him start drinking again and watching it escalate.