The reason that he never understands why Elly wants him to be angry with her is that it never occurs to him is that he's married to a woman who needs to be upset about things in order to make sense of the world. She quite simply cannot comprehend the idea that people don't want to yell and scream about something that they can't do anything about because she was raised in an environment wherein her thin-skinned mother got on her case for every little God-damned thing because she was trying to stiff-arm CHAOS and the idiot child who is at the same time a defiant nitwit and a pathetic brown-noser that Elly will always be thinks that getting hollered at for nothing is normal.
He also has distinct trouble noticing that Elly married her own kind when it comes to the whole "not believing in honest mistakes" thing. Granted, we don't see him thinking that a simple goof-up is part of a plot to destroy him as much but he does think that everyone is out to get him. This makes talking to him an exercise in what Robert Ringer called speaking Sanskrit; when he says "You can come to me with your troubles because I'm an understanding man", he joins Elly in really meaning "If you do something that inconveniences me in the least, I'll treat you like a red-haired mule."