Sansa is getting a new wardrobe courtesy of Cersei and/or Maergery. It turns out life is not so bad now that the Tyrells are in town and Sansa has lots of new friends who are nice to her. So much so that she's told Dontos she doesn't want to escape any more.
She sees herself as far more worldly-wise than the various Tyrell girls, since she has seen battles and her dad's head chopped off, and she has a point. She keeps warning Maergery about Joff but Maergery seems unconcerned and thinks her brother the Flower Knight, now kingsguard, will protect her from him, presumably by turning kingslayer and throwing the realm into new chaos. But how much has Sansa really learned? Despite Dontos' warnings that he's only after Winterfell, she thinks marrying Willas will be lovely. But he might well be just as much of a monster as Joff.
Anyway, she's got until the night of Joff's wedding to decide, because that's when Dontos' boat will be ready to rescue her. It'll be the best wedding Walford, I mean Westeros, has ever had!