Wait I dont get it. Why is she helping her sisters' fiancee who she said that is plotting to kill her??
It doesn't matter because she is right now a carrier bird, who's task was to deliver a letter. And if she didn't, there is a high chance to lose the war. Because in a war, the most important thing is not weapon and dominance but communication.
And she wanted to help her kingdom. She couldn't just run away from everybody who has been threatening her in her past.
Wait I dont get it. Why is she helping her sisters' fiancee who she said that is plotting to kill her??