I like that last part of the quote too. Emma knows she and Jane can never be close friends -- but realizes that she should pay Jane more attention out of kindness and social obligation towards a less fortunate gentlewoman of her own age.

For Emma, as the leding lady in Highbury, who "can choose with whom to associate", it is not a choice of either becoming intimate friends with Jane or neglecting her -- there is a middle ground between these two. Not that Emma completely neglects Jane -- I'm sure she invites Jane along whenever she invites Miss Bates for her father's sake. But as they are of the same age, I strongly feel that it would have been both kind and very proper to occasionally invite Jane to Hartfield without her aunt.

Emma's attentions to Jane so far seem merely as an extension of the Woodhouses' attention to Miss Bates. Emma finds Miss Bates tiresome and seem to dislike Jane more for it, instead of pitying her for having such a tiresome aunt. Emma is surprised that Jane should accept Mrs Elton's attentions and tolerate her as she seemed to do, but as Mrs Weston said --

"We cannot suppose that she had any great enjoyment at the Vicarage, my dear Emma -- but it is better than being always at home. Her aunt is a good creature, but, as a constant companion, must be very tiresome. We must consider what Miss Fairfax quits, before we condemn her taste for what she goes to."