I can only imagine feeling comfortable after 3.5 good years and then--boom!
I've never been married to an active alcoholic. One thing I have learned from years of belonging to SR is that for any alcoholic in recovery, the possibility of relapse is always present--that it takes vigilance to maintain sobriety.
Interestingly, many alcoholics in recovery that I have encountered are very happy, thoughtful, well-balanced people because they have taken the time to truly evaluate themselves and work on their own flaws. The problem becomes when they lose that forward momentum and fall back into their old drinking habits--their old coping mechanisms. There is always that risk when involved with an alcoholic.
I am so sorry for what you are going through right now. I suppose the relief is that no all decisions have to be made today, right? Once you are ready, then you can decide exactly what you want to do and how you can make your life one that you love.
Hang in there! Sending hugs and prayers!