Boy, you are right. This scene does have an impact.
It's interesting that Marianne, after learning that Willoughby did not show up to the party where he was invited, descended into an insensibility of everything around her.
She sat by the drawing room fire after tea, till the moment of Lady Middleton's arrival, without once stirring from her seat, or altering her attitude, lost in her own thoughts and insensible of her sister's presence:
It surprises me that when she gets that first glimpse of him at the party, all is forgotten if only momentarily.
At that moment she first perceived him, and her whole countenance glowing with sudden delight, she would have moved towards him instantly, had not her sister caught hold of her.
It's interesting to note too, that it is Elinor who is too shocked to speak. Even though she suspected something was wrong with the whole relationship, this was beyond her imagination.
He approached, and addressing himself rather to Elinor than Marianne, as if wishing to avoid her eye, and determined not to observe her attitude... Elinor was robbed of all presence of mind by such an address, and was unable to say a word. But the feelings of her sister were instantly expressed.
I do think that S&S2 comes pretty close also. But now I think I might put it on, and watch Emma Thompson's face in that scene.
I noticed again how Elinor is overcome with emotion when the letter arrives the next morning.(ch. 29)
Elinor, who saw as plainly by this, as if she had seen the direction, that it must come from Willoughby, felt immediately such a sickness at heart as made her hardly able to hold up her head, and sat in such a general tremour as made her fear it impossible to escape Mrs. Jennings's notice.
And now for a couple of technical questions...
Elinor, expecting every moment to see her faint, tried to screen her from the observation of others, while reviving her with lavendar water.
If you're trying not to make a scene, why bring out the lavender water? Did they just put a vial of it under the nose of the person for them to smell, or apply it somehow? This notion too, of women being overcome often enough that someone would think to carry lavender water around, is weird to me.
they could go directly to their own room, where hartshorn restored her a little to herself
What is hartshorn?