When the company disperse—by which time Mr. and Mrs. Veneering have had quite as much as they want of honour, and the guests have had quite as much as they want of the other honour—Mortimer sees Twemlow home, shakes hands with him cordially at parting, and fares to the Temple, gaily. (9.17.55)
In the book's final scene, we join one of the Veneerings' dinner parties, where the whole crowd is busy criticizing and condemning the marriage between Eugene Wrayburn and Lizzie Hexam. Eugene comes from a good London family and Lizzie is the daughter of a riverman… and this (mis)match has all of London's upper crust clutching their pearls, reaching for their smelling salts, and saying "Goodness gracious!"
All of society seems to condemn the marriage as unnatural until the shy Mr. Twemlow speaks up in defense of love. Get it, Twemlow. You're awesome.
The whole company eventually gets up and leaves, sickened by Twemlow's unconventional thoughts on love. But Mortimer Lightwood, Eugene's best friend, is happy that Twemlow had the courage to speak up and gives him a figurative pat on the back. As the party ends, we realize that love has scored a victory against pride, since Lightwood and Twemlow have been convinced that love is more important than social status.
There will always be people who think status is more important, but we don't need to worry about what these people think. They can have their caviar and champagne; we're content with the thought that true love conquers all.