Arriving at the ball at Netherfield, Elizabeth is disappointed to realize that Wickham is not at the party. Elizabeth blames Darcy for Wickham's absence. She endures two dreadful dances with Mr. Collins.
Because Elizabeth is set in her own prejudice, she interprets everything against Darcy and blames him for everything.
Darcy then asks Elizabeth for a dance. Caught by surprise, she accepts. Their conversation is short and abrupt. Darcy is uncomfortable when she brings up Wickham.
Darcy's dance invite shows his growing feelings for Elizabeth. But now Elizabeth's prejudice against him is in full effect.
Afterwards, Caroline approaches Elizabeth about Wickham. He wasn't wronged by Darcy, she says. On the contrary, Wickham treated Darcy terribly and now Darcy has nothing to do with him. Jane, who has been speaking to Bingley, tells Elizabeth the same story: the fault, whatever it is, was Wickham's. But Elizabeth refuses to believe it.
Elizabeth now has evidence, from various sources, that it was Wickham, not Darcy, in the wrong. But Elizabeth pridefully chooses to go with her prejudices against Darcy and for Wickham.
The rest of the evening is a disaster. Mr. Collins rudely introduces himself to Darcy and later pontificates to the whole assembly. Darcy overhears Mrs. Bennet talking about Jane and Bingley like they're already married. Mary insists on playing the piano, and does so awfully. And Mrs. Bennet conspires to be the last to leave. Realizing that her family's reputation is falling lower than ever, Elizabeth is mortified.
Elizabeth and Jane have a social grace that their family members sorely lack. If Darcy's major concern about Elizabeth was her family, the Bennets do everything to prove that his prejudice against them is accurate.