Well, here are some of the options the creators can use e.g.
1. She gonna get depressed and her cheerful personality gonna change.
2. She gonna remove this event from her memory. (the repression mechanism)
3. She gonna get angry and want to get revenge. (not very likely considering her personality)
4. It'll be something less serious and she gonna recover from it fast and she'll decide to stop the war. (the most probable option in my opinion)