KJ-
I wish I had answer for you, but can only offer assurance that I am in a similiar position, questioning the deapth of "aid" in my acts.
My abf was broke (obviously) but was in need of getting to rehab. So, I paid for his train ticket, his cab and a couple packs of cigarettes so he could get there. Upon leaving rehab (entirely too early) I rented a car for an astronomical amount of money and picked him up. (At the time I believe I was deeply in the web of MY addiction ~ need to control- I wanted to be the one to pick him up)
From your inital post it sounds as though his recovery is more about proving to YOU that he is actively doing things to maintain recovery and not "doing what he needs to do" to keep himself clean. I believe that addicts have their priorities completely out of whack and despite all the selfishness that results from drug addiction, at their core they are using drugs to manage feelings.
If he can drive himself - he should be attending by himself- regardless of whether or not you KNOW and SEE and validate that he is actually going to a meeting.
I am beginning to learn (SLOWLY) that if our addicts are truly serious about recovery than only THEY can choose it. I find myself constantly still yapping- giving advice- telling my addict personal insights as to what he he has to look forward to in his life and what roadblocks he must remove to move forward, when in reality I am GIVING to someone who I already know won't stop doing what they're doing until they're good and ready to change.