why is zeena dissatisfied with mattie? how does this dissatisfaction affect zeena's behavior toward her?

Matte and Ethan have a "thing" going. Well, it's not obvious but perhaps Zeena catches on to the fact that her husband actually has some life in him. Zeena claims that Mattie is a bad housekeeper. In turn Zeena is even colder to her than she usually is to everyone else.