Welcome to SR, nowell.
I may be wrong here, it it is my understanding that sober means no drugs and alcohol. And drugs like pot. It is a drug, right? SO how can he be sober and have a strong 12 step program if he's smoking pot?
And in all honesty, it sounds as if he let you go to free himself for whatever he is up to. My internal BS radar went off all throughout this post. Why would a friend confront him on using drugs if it wasn't true? And you all are my age...my friends don't BS. We're too old for that nowadays. So I lean toward that friend knows a lot more about these concerts than you do.
It sucks to be caught off guard, I know, because I was too, by an addict. But you know what? Everything happens for a reason, and I am far enough away from my divorce to see that I have dodged a bullet and can go on with my own life, without the ball and chain of addictions dragging me under.
Reading between the lines in your post, I sense a lot of things being "off" here. More to be revealed, I would bet.
In the meantime, you sound like you have a lot to offer folks here, so please keep coming back, and hang in there. It does hurt less and less as time goes by.
~T