The very mention of anything concerning the match threw her into an agony of ill-humour, and wherever she went she was sure of hearing it talked of. The sight of Miss Lucas was odious to her. As her successor in that house, she regarded her with jealous abhorrence.

– Jane Austen

Pride and Prejudice, Chapter 23. Mrs. Bennet is said to be in a "most pitiable state" over Charlotte Lucas’s engagement to Mr. Collins. Had Mr. Collins married one of her daughters, the Bennets home Longbourn would at least have remained in the family after Mr. Bennet’s death. But with Charlotte to marry the man who will inherit Longbourn, Mrs. Bennet cannot stand the sight of her.