feeling weak to put up the fight

Hi, I suggest you to find some other more efficient way of solving problems rather than fight. Your wife must have her own reasons why is she accusing you of being responsible for every problem you two have. Try to indicate her your side of the story, maybe you are not communicating in god way. After surgery or other illness, people tend to be more vulnerable, so she might be acting as usual and you are over reacting. Often, wives expect too much, specially if they get married for social reasons, to get higher on social scale.