It sounds like it might be time to take this up with her supervisor, you will need to be calm, professional, relating the situation re: a mistake was made that could have been corrected, and it negatively impacted a client sounds appropriate. Somehow, you do need to separate your personal feelings from what matters at work. Not easy. (another dept. you want to work in? request a transfer?)---people usually do leave their supervisor rather than their job...but you have been there a long time...