Welcome to SR,
My husband still drinks, but I had to throw myself into working the AA steps with my whole heart and soul (what was left of it).
If you save yourself, you son will have at least one parent...without it, he has none.
You can be the best example of how AA works. Perhaps your husband will want what you have after he sees you sober and happy (happier?).
I had to sober up, I had too much to loose. My life was spinning out of control - it was insane. Maybe you are that way too? Sounds like you have a nice husband (even though he's a drinker) and a nice son. You sound like a real decent person too and well worth all your efforts to make an AA program work.
Just because it didn't work once, doesn't mean it couldn't work now.
Good luck. Come here to share your troubles and your success!