My sense is he more than likely is manipulating you. That's what addicts do. Oh, so he stopped the drugs and drinking's ok now? Be glad you don't have to live with his being a drunk. Out of his mind on drugs or out of his mind on alcohol is still out of his mind.
He's trying to do a number on your head. Don't let him.
You've made a wise decision in not driving him and have done nothing wrong. He'd like you to think you did.