at this point, that she has heard at least some version of Mr. Wickham's story. She tells him as much, when she tries to prick him with the comment about how Mr. W. has been unlucky enough to lose his good opinion....etc.

I have also always, groundlessly and for my own satisfaction only, assumed that the Meryton grapevine gave Darcy some clue after the assembly that the "not handsome enough to dance with" comment was overheard and made fun of. And he still doesn't know what to make of the few conversations he has had with Elizabeth, especially the ones at Netherfield during Jane's illness.

So, from his point of view, her character sketch would be based on the following views alone:
- his behavior at the assembly
- her offended pride at same
- his admission that his temper was implacable
- her feeling that he was making fun of her for liking to dance
- Mr. Wickham's story