please keep in mind, he's BEEN to rehab and he HAS a psychiatrist, these are two excellent sources of SUPPORT should HE choose to get sober again. it's a trap WE fall into that WE are all they have...that WE are their only source of support. forgetting somehow the size of the planet and all that.
you cannot cajole him out of this. if YOU were really his solution, he'd be sober. but he's not, because this is not your job, not your problem to fix. if you feel he is truly a danger to himself, call 911 and have them do a care call. right now I don't know if you are "enabling" but you are keeping yourself caught in his trap. probably best to simply send the same consistent message - contact the rehab, or contact his psych dr or contact NA and they can help him.