I let other people read my personal statement, but since the best statements are tailored for your course, I was fine sharing it with my best friend (he was applying for the same course but I trust him implicitly) and other friends who were taking other courses.
However she shouldn't share it with the class. It's for you to share with who you want, at your discretion, to help someone else with their style, not their content. If she does it without your permission punch her in the face, or report her.