She thought of what had just passed with anxiety and distrust.

Willoughby's behaviour in taking leave of them, his embarrassment, and affectation of cheerfulness, and, above all, his unwillingness to accept her mother's invitation, a backwardness so unlike a lover, so unlike himself, greatly disturbed her.

One moment she feared that no serious design had ever been formed on his side; and the next that some unfortunate quarrel had taken place between him and her sister;--the distress in which Marianne had quitted the room was such as a serious quarrel could most reasonably account for, though when she considered what Marianne's love for him was, a quarrel seemed almost impossible.
But whatever might be the particulars of their separation, her sister's affliction was indubitable; and she thought with the tenderest compassion of that violent sorrow which Marianne was in all probability not merely giving way to as a relief, but feeding and encouraging as a duty.
In about half an hour her mother returned, and though her eyes were red, her countenance was not uncheerful.
"Our dear Willoughby is now some miles from Barton, Elinor," said she, as she sat down to work, "and with how heavy a heart does he travel ?" "It is all very strange.

So suddenly to be gone! It seems but the work of a moment.

And last night he was with us so happy, so cheerful, so affectionate?
And now, after only ten minutes notice--Gone too without intending to return!--Something more than what he owned to us must have happened.