Firstly, I don't think Ben raped anyone. There is a reason he wasn't even charged with anything. He obviously had (or has) some issues with alcohol and decision making, but if he raped anyone he would have been charged.
Secondly, it is clearly her religious beliefs since she still lives at home with her parents. He is just taking some of the spotlight off of her and putting it on him. The story is now about him and not her, which obviously benefits him, but also benefits her.