In this group read, I have been focused on shifting identities and social classes, and in Jane Fairfax, we see a character who has had to adapt repeatedly to change and is about to do so again. Rescued from Highbury and poverty by the Campbells, she has been educated along with their daughter -- but destined for such a different end. Miss Campbell has married, and no doubt her husband is prosperous; Miss Fairfax now faces the loss of the world she has been living in and must start to look for employment as a governess.

It's no wonder she's too reserved and discreet for Emma's taste. She's been an outsider since childhood, always knowing that while her childhood playmate was destined for a wealthy husband and a life of luxury, she herself was being brought up to serve such people.
How much Jane must have witnessed, even if she didn't have a crush on Mr. Dixon, and how much will she have to keep quiet about when she finds a place as governess to someone else's children. One does wonder why she is depriving herself of a trip to Ireland to see her friend, especially since it is possibly the last such chance she will have.
It's interesting to note, too, that Jane in fact has been out in the world much more than Emma, for all her wealth. We hear of a boating party in Weymouth as well as the chance to go to Ireland with the Campbells, while Emma, because of her father's fears and health issues, has never even been to the sea.
At this point, we're still being teased with Frank Churchill. Jane knows him but won't say anything, not even to tell Emma whether he's handsome or agreeable, which seem like innocuous enough questions. Jane's right -- we will have to judge for ourselves.