Who is Barbara from Friend of My Youth: Stories and what is their importance?

Barbara is Murray's wife and potentially Victor's lover, though the reader never learns whether she cheated on her husband or not. She is quite a cold woman with whom it is not easy to get along. She does not make friends easily, and takes little interest in anything except reading. She has very little passion for anything in life. She likes to read but sees no point in college, has no desire to get a job, and seems to be content living a fairly monotonous life. Murray reveals that she also has little passion for him during sex, and that he hates it when she wears seductive clothes and it seems like a lie. Murray worships Barbara, but at the same time does not really seem to understand her.