Want my initial reaction?
Thank your lucky star or whatever higher power you believe in. Doesn't matter who files, the important things are a) that you don't want to be married to an alcoholic and b) very soon, you won't have to be anymore.
I'm sorry if that sounds really harsh -- but you can't worry too much about what people might think. I have a fairly large extended inlaw family that sees me as The Traitor That Abandoned Their Relative When He Needed Me Most. They're not the ones that had to unclog his sink after he puked in it five nights a week. So I really can't be bothered with their opinion. Really.