... and Emma, and what do I find?

Chapter 10:
Oh! yes; we are always forced to be acquainted whenever she comes to Highbury.

ch. 12:
she had nothing worse to hear than Isabella's kind inquiry after Jane Fairfax; -- and Jane Fairfax, though no great favourite with her in general, she was at that moment very happy to assist in praising.

Ch. 19:
But now she made the sudden resolution of not passing their (Bateses') door without going in -- observing, as she proposed it to Harriet, that, as well as she could calculate, they were just now quite safe from any letter from Jane Fairfax. [it was a couple of days before the usual letter]

She had not been prepared to have Jane Fairfax succeed Mr. Elton; [She had been expecting a merely tedious dissertation on all the residents of Highbury]

She regained the street -- happy in this, that though much had been forced on her against her will, though she had in fact heard the whole substance of Jane Fairfax's letter, she had been able to escape the letter itself.

Ch. 20:
Emma was sorry to have to pay civilities to a person she did not like through three long months!

It was a dislike so little just -- every imputed fault was so magnified by fancy, that she never saw Jane Fairfax the first time after any considerable absence, without feeling that she had injured her; ... These were charming feelings, but not lasting. Before she had committed herself by any public profession ... every thing was relapsing much into its usual state.... She [Jane] was disgustingly, was suspiciously reserved.

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And only after the last of these comments (most taken from Emma's stream-of-conscious) does Jane actually show in person the reserve she's accused so bitterly of! -- in response to an interrogation many of us feel was impertinent, even aggressive.

Do you really believe a young woman of "good understanding" (beginning of ch. 20) who has been treated this way her whole life has no reason -- indeed, has no obligation -- to be reserved, even suspicious?