Much of the conflict in the novel, between Miss Bingley and Lizzy, is due to their differing views about how a woman should behave.
Miss Bingley is a wealthy lady of fashion, she has accomplishments and flirts with Mr Darcy in a conventional manner. She feels that Lizzy is deliberately flouting 'correct' behaviour by walking several miles alone - this is her "conceited independence".
Lizzy, as the female protagonist, challenges the norms of behaviour. She demonstrates intelligence, independence of thought and a disregard for the "decorum" of fashionable society.
Austen is critical of the superficial Caroline Bingley, and demonstrates her belief that Lizzy's traits are the more admirable by using them as the catalyst for Darcy's attraction.