ISOHumility: My mama heart goes out to you right now. You know where your son is headed, but he does not know.
I have heard it said that having a good bit of sobriety is the best way to ruin a good relapse. I'm sure you have a hard time hanging onto that one right now, just thought I'd throw it out.
I will be praying for you and for your son. May you find some peace and serenity right now. How fortunate for your son that you are in recovery (and for you too!!).