Why is Mrs. Jensen contemptuous of men?

In the
book, Mrs. Jensen is Lorraine's mother. She's a private nurse and often works the night shift.
Her patients are usually elderly and terminally ill. Lorraine and her mother have a difficult
relationship, as Mrs. Jensen is a deeply unhappy woman. According to Lorraine, her father left
them fifteen years ago when his parents got a legal separation. Since Lorraine's father is now
deceased, Lorraine states that the separation between her parents is permanent.

Mrs. Jensen has a great distrust of men due to her husband's actions during their
marriage. Accordingly, he had contracted a venereal disease while she was pregnant with
Lorraine. She discovered his illness when the doctor called and warned her not to engage in any
sexual intimacy with her husband until he was cured. When Mrs. Jensen found out that her husband
had actually cheated on her, she filed for a legal separation. According to Lorraine, this is
the main reason that her mother is contemptuous of men. Mrs. Jensen equates all men with her
faithless husband; she sincerely believes that all men are untrustworthy and that they are only
interested in sex.

Because of her hangups about men, Mrs. Jensen is always
warning Lorraine about boys. She tells Lorraine not to get into a car with any boy and warns her
that men "have dirty minds, and theyre only after one thing." Lorraine imagines that a
good psychiatrist would be able to help her mother, but she concludes that her mother's problems
are so "deep-rooted shed need three years of intensive psychoanalysis" just to see
some results.