Hello! New here! Long time lurker, first time poster
I'm going to go against the grain here. Pictures are very personal things. I would be furious if someone stole mine and edited them. If she's editing them to just crop you out, who says she's not editing them to add something that could be embarrassing for you? She's messing with your image, stealing your memories and taking the time to modify your
Yes, she's creepy, but maybe she is because nobody calls her out on her rude behavior. She stole from you.
I really think you need to notify FB with at least her name and your ex's name. I'm sure there is something they can do. And if not, at least they can give you suggestions on how to make sure this situation never happens again. For instance, on Myspace, you have the option to make your photos "unsharable." Basically so that nobody can save them to their own computers.
Notify FB, get your pics back, find out how you can keep your pictures from landing in this situation again, and block block block.