I'm not 100% if this fits into what you're looking for, but the two movies that came to my head were "Girl Interrupted" and "Speak". I just watched "Speak" a few weeks ago, it has Kristen Stewart in it... from Twilight. She actually does a really good job at playing the role of a selective mute girl. It reminded me a lot of me in high school, though I don't think it revolves around SA in particular much.
Girl Interrupted is one of my all time favorite movies. It's sort of hard to explain what it is, but it does revolve around some disorders. Angelina Jolie is in it too. Check them out on IMBD;
- Girl interrupted