Just stand by her, she's going to need someone there for her. If he didn't use a condom, get her the morning after pill, quickly! it's only affective for a period of time, once you've had sex. If they have a video of it, get a hold of it and show it to the police. They'll take care of the rest.
All you have to do, is be there for her, be there for her when she cries and keep telling her that it's ok, the police will catch the guy and he will be punished for what he did.
Good luck, I hope everything goes ok with your friend and I hope they catch that asshole.
-John Cena54
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