I think she tries going on a few dates, but there’s no real spark. Then something happens with Lilly where her medicine was fake, and Blair & Chuck conspire to figure out why. He tries a romantic gesture about meeting him at the top of the Empire State Building to start over, like an Affair to Remember. But if she doesn’t show, it’s over between them. He buys an engagement ring, flowers, but she doesn’t show because Dorota has her baby. She shows up later, and they kiss & make up, but figures out that Chuck had had meaningless sex with Jenny right before Blair got there.
