Shortly after Queen Chrysalis' defeat at Canterlot, her army is demoralised and hungry, and the Queen herself is at her wits end - having locked herself in her bedroom, presumably to spare her subjects from her upcoming mental break in a short moment of compassion.
The Queen that leaves the room is far different from the one that entered it.
Queen Chrysalis, seemingly revitalised in her entirety, declares a change in course for her and her subjects. She promises to lead them to a new battlefield... and she swears victory in her name.