Ursula's mother, Sylvie, is traditional to a fault. She hates Izzie (often fantasizing about her getting kidnapped by "white slave traders" (4.66)) because Izzie is what Sylvie believes to be a woman of loose morals. Sylvie's also cruel to Ursula when she gets pregnant, even though this only happens because Ursula is raped.
Despite promoting her traditional values, Sylvie is quite the hypocrite. She's uptight about Izzie's behavior, but she has been cheating on her husband for who knows how long. Seriously—the evidence comes in spades:
Who's a loose woman now, Sylvie? Uh-huh… She acts like being a wife and a mother is her fate, but she isn't very nurturing in either role. And when her husband and one of her sons (Teddy) die, she kills herself by overdosing on sleeping pills. We guess if you live your whole life as a wife and mother, and your husband and son die, you have nothing left to live for, though in some ways this suicide is the most devoted she ever truly seems to those roles.