He hadn't meant it as a brush off. At all. He really wanted to not be hungover after sleeping with Jo, and be in full possession of his faculties. Dean was pretty sure that if he kept drinking, standing was going to be a struggle eventually.
Think I'd better try to sleep this off.
His eyebrow rose. Maybe he really should just leave it, for now. "Okay," Dean said. He took another few drinks before leaving the cup un-refilled, and climbing into bed, too. He put his arms around Jo and snuggled into her.
He got it. Why it had to be her, if he was going to settle down at ALL. Nobody else was going to really understand without getting mad, because they weren't gonna be a hunter, or they wouldn't know enough about his family, or a billion other things.