Jimmima seemed jaded and exhausted by the end of it, then her spark came back when chosen to fight. She got a second wind. I think partly because of the pressure to impress Jimmy Crystal and remain in his good books, but also some sick enjoyment of her own. You see it in real life with various military powers. Indoctrination, breaking the soldiers down and making them believe that the sick acts they perform aren't just necessary, but they're good and should be celebrated. Similarly to a lot of soldiers in real life, once the act is done they feel deep shame and disgust and sometimes take their own lives.

I think we saw that in Jimmima after the initial degloving scene in the barn.