Quote 22
And she wept all day long, from chagrin, from regret, from despair, and from distress. (6)
In case you needed any additional proof that Mathilde is miserable, she spends all day crying. Her life has essentially nothing enjoyable in it.
Quote 23
She danced with delight, with passion, intoxicated with pleasure, thinking of nothing, in the triumph of her beauty, in the glory of her success, in a sort of cloud of happiness made up of all these tributes, of all the admirations, of all these awakened desires, of this victory so complete and so sweet to a woman's heart. (54)
This represents Mathilde's one moment of genuine joy. It's just about the only such moment in the whole story, and forms a high point between two long bouts of unhappiness.
Quote 24
And he went out. She stayed there, in her ball dress, without strength to go to bed, overwhelmed, on a chair, without a fire, without a thought. (79)
The object which made Mathilde's glorious night possible has become her worst nightmare just a few hours later. She's so traumatized she can't even get out of her chair. How quickly the situation reverses. The fact that Mathilde's hasn't even changed out of her lovely ball gown captures that reversal in an image.