During the conversation at dinner, Elizabeth accepts, but sees through, the empty concern that Mrs. Hurst and Caroline show for Jane. Still, she is grateful to Bingley for his sincere interest in Jane.
Elizabeth continues to value character over class. She seems to have good intuition about people's true character.
When Elizabeth returns upstairs, Mrs. Hurst and Caroline criticize her looks, manners, and judgment. Mrs. Hurst says she does really like Jane, but that her family situation—having few connections and no money—will block her hopes of making a good match. Darcy agrees.
The high class women show their prejudice. Though Mrs. Hurst speaks as if in sympathy with Jane, she's deviously trying to ruin the chances of either Bennet sister by mentioning their "family situation."
Elizabeth returns downstairs in the evening, choosing to look through some books instead of joining in cards. Caroline, who has been absorbed with Darcy, asks him about his estate, Pemberley, and about his sister, who she deems a very accomplished woman. Darcy says he knows few women who are really accomplished. Elizabeth asks his definition of the term and, stunned by the long list of qualifications, expresses witty surprise that Darcy could know anyone who with all of those characteristics.
By choosing books over the social fluff of cards, Elizabeth shows her inner substance. Plus she has the common sense to recognize the foolishness of society's unreasonable ideals about women. And she has the courage to say so in company. These characteristics distinguish her more than useless accomplishments would.
When Elizabeth leaves again, Caroline accuses her of using mean tactics to raise her own status.
Ironic, because that's actually what Caroline is doing. Caroline wants Darcy, and puts down others to elevate herself in his eyes.