What is the relationship between Kumalo and his wife?

"Kumalo and his wife have lived in relative harmony, and their careful budgeting and saving shows their organization and cooperation. The arrival of the letter, however, stands this simple order on its head, as Kumalo and his wife argue and are forced to squander their savings. In the station and among the simple country folk on the train, Kumalo is master of his domain, but every time he thinks of the city and its dangers, he becomes small and weak, an old man." (1)