I blame it on the cat.
What did the cat have to do with anything?
I had a fight with my wife that lasted for more than a few hours.
Having a fight with your wife was likely caused by a misunderstanding between the both of you. You should take responsibility for any part of the argument that was your fault. You shouldn't blame a cat for a problem between you and your wife.
It was about the cat.
Well if the cat is the problem have you talked about it or tried to train it? If it is about cleaning the litterbox I think you guys should take turns to keep it fair.