Marriage issues?

My dearest parents, after several years of marriage, are now fially coming to the realization that they are not satisfied with each other. My father has told me that  my mother is very foolish, but I thought my father knew that when they got married. My mother believes that my father is very disrespectful, but has he not always been that way? It dissapoints me that they are having problems, but my sister Elizabeth is extremely infuriated. She has extremely high expectations of marriage, and she is very ashamed that not even her own parents meet those expectations.We have always known that neither of our parents were really romantic, but why our all these feelings being brought to the surface at this point?