She's also badly wounded and exhausted, so it's probably a bit literal too from the confusion that causes.So Shurine at the start of the story was very much fighting because she was told to, she had no motivation herself she was just a mercenary in it for the love of the game.
In this fight though that isn't quite enough and it represents the moment that Shurine realises something we the audience have known for a few chapters. That she's fighting for Lutecia her wifey.
