It's Your Fault, Not Mine

This is an annoying habit! It sounds, however, as if your own defensive response to his blaming behavior is inflaming the situation. Next time he blames you for something he did, ask him to explain himself better, so that you can understand why he thinks it's your fault. There may be a kernel of information there to help you see his point of view. For example, if he blames you for a lie he told to cover something up, it is useful to hear what he's thinking. You might discover that he feels he can never live up to your standards, that he is embarrassed to tell you that he didn't do something he had promised you, or that something you say always triggers a defensive response.

Talk with him about these core issues, instead of arguing about his habit of blaming you. If you use this approach regularly, you may find that he has less reason to blame you or change the subject, and is more willing to talk about his difficulties.