You are a great mom. Anyone who says otherwise is ignorant. You've survived more with one kid than most moms will have to deal with from all their kids put together.

As you said, at least he's not physically abusing you any more. One step forward, at least. That gives me hope about him, actually. I think he's just in that "I know everything" stage, I went through that stage.

I agree with MM, though. Make him give you a list of things he wants and when he's done well, then buy him the thing instead of giving him the cash. Let him know straight up that you're not paying him to buy pot or alcohol or anything like that. If he wants cash, then yeah, get a job. Maybe keep the conversation on hold until you're both calm, though.