[MachoPoodle]

I don't see it as a scale where the blame has to be divided up. Lee is as much a ****tard as he's ever been and none of his behaviour is Casey's fault. On the other hand, after it became clear he was playing her, and especially after he went all around the house lying about her, Casey is being an idiot to want anything to do with him now she knows full well what he's like. So Lee is still responsible for all his actions, just as Casey is responsible for hers.