What does the author reveal in chapter 19 about the nature of the Bennet marriage?

Elizabeth's father had married her mother because he was captivated by her beauty, but her weak understanding soon made him lose all real affection for her. Mr. Bennet derives his enjoyment from books and the country. Elizabeth has always recognized the impropriety of her father's behavior as a husband, and is now especially aware of the disadvantage that such a marriage has had on the children. She faults her father for not having used his talents to at least preserve the respectability of his daughters.