Regarding that last meeting between Willoughby and Marianne at Barton Cottage in chapter 15: did anyone else get the impression that Willoughby told Marianne a different story than the one he told the rest of the Dashwoods?
If he told Marianne that he had "no idea of returning into Devonshire immediately", why would she expect him, in the next chapter, before "many weeks"?
But if he did say something different, what could it be? Whatever it was, it simultaneously threw her into great despair, yet had her expecting him back shortly. Any ideas?