If the beginning of The Disreputable History of Frankie Landau-Banks opens with Frankie meeting a cute boy at the beach, then the ending turns this moment on its head. In the end, we see Frankie having an exchange with her ex-boyfriend Matthew that's sad and fraught with tension. Frankie wants to reach out to Matthew and connect even after everything that happened between them, but Matthew rebuffs her:
Matthew would rather let her keep the shirt than interact with Frankie for another second. He hates her that much.
He turns away, and the dogs follow.
Frankie chokes back tears. She doesn't want the shirt anyway. (46.56-58)
Frankie starts crying over this; after all, she's still a fifteen-year-old girl whose former boyfriend (a gorgeous, popular senior) doesn't even want to talk to her anymore. But the ending really becomes poignant when Frankie stops crying because she realizes that she doesn't need Matthew after all:
It is better to be alone, she figures, than to be with someone who can't see who you are. It is better to lead than to follow. It is better to speak up than stay silent. (46.60)
That she doesn't regret anything she did, because she was being true to herself and she doesn't need a boyfriend who wants to keep her docile and sweet anyway. It's more important for her to be Frankie Landau-Banks than to be Matthew Livingston's girlfriend.