To answer your question directly I was sober just short of a year while going to AA. Stopped going because I believed that my atheism and AA principles were at odds. Stayed sober a few weeks...and then off again for almost two years.
I'm back at AA now, have found agnostic/atheist on-line resources, and relying on AA for face to face and peer support.
I put my return to drinking down to stopping meetings.