Full of this whim was thoughtful Madeline: The music, yearning like a God in pain, She scarcely heard: her maiden eyes divine, Fix'd on the floor, saw many a sweeping train Pass by—she heeded not at all: in vain Came many a tiptoe, amorous cavalier, And back retir'd; not cool'd by high disdain, But she saw not: her heart was otherwhere: She sigh'd for Agnes' dreams, the sweetest of the year.
Aha—our Lady has a name: Madeline.
The party may be full of "argent revelry," but Madeline's got bigger fish to fry (like "Agnes' dreams," those visions of her future husband). She's paying zero attention to either the "sweeping trains" (which refers to the skirts of the other women, not super-clean locomotives) or to any of the young guns trying to hit on her.
The music is back, but unlike our Beadsman, Madeline neither hears nor appreciates it.
Also, the music feels different this time around: it's now described as "yearning like a God in pain," and that sets a very different mood, especially now that you're thinking about Madeline, a girl on a one-track mission to see her hubby-to-be. Also, that "like" in "like a God in pain" clues you in to the fact that you're looking at a simile.
While the other guests are described in terms of their "high disdain" or their material luxury (Tiaras, people? How many times have you worn one to a party?), Madeline's described as having "divine maiden eyes," setting her apart as a very different sort of person than the rest of these folks.