He's an absolute mess right now, but I think with him it is all between the ears. He's overthinking the game. I think what he needs is a slump buster. He needs to head out to a club (on the road, of course) with some teammates and they need to do the "dollar a pound" thing. Get his mind off the game, so that the next time he's on the floor, he isn't thinking about making shots or defending guys. He needs some garters a la Nuke Laloosh.
He is making poor decisions, forcing shots, losing track of his man and then reaching in, he's just not into the game. The second year is the toughest, especially when you've had a few injuries. He needs to understand that and let the game come to him. You can't force it.