How injured was she? Is the army/marines/air force/navy/coast guard (you didn't specify which armed forces she was in) not taking care of her? It won't be easy to get her removed, that's a pretty big agreement you sign away. They want you to learn to be tough and tough through things in life. By telling you this I mean that it's going to take something really big for her to become inactive. What was her injury? Or is it something too personal?
Good luck!