Why is Angela afraid to tell her mother she doesn’t want to get married?

Twenty-year-old Angela is about to get married to Doctor Deere. She doesn't really want to but her mother is puhing for it. To Forty-two-year-old Grace Windsor, status is important to her, and she fancies herself an interior decorator. She dotes on her older daughter, Angela, but is dismissive of her young daughter Turtle. Although she claims Windsor as her maiden name, she was actually born Gracie Windkloppel.