Elizabeth and Jane write to Mrs. Bennet to send their carriage to take them home. Mrs. Bennet, still scheming to have them stay, replies that it isn't available. So Elizabeth and Jane have to borrow Bingley's carriage instead.
Mrs. Bennet's schemes to get Jane married to Bingley force her daughters to be beggars, making the Bennet family as a whole look bad.
Darcy is relieved: he is starting to worry that his attraction to Elizabeth might show, so he remains distant for the short remainder of her stay.
Darcy has not overcome his prejudice against the Bennet's low connections.
Though Mrs. Bennet is disappointed that Jane and Elizabeth didn't stay, Mr. Bennet is glad to have them back. He had missed their conversation amid Kitty and Lydia's infatuation with anything related to the regiment.
Mr. Bennet wants to ignore his younger daughters' interest in the regiment, to remain detached from anything that strikes him as ridiculous. This will come back to haunt him.