Sometimes people lie. Sometimes they lie about horrible things. A mother making her kid sick to get attention, for example...but that doesn't mean that there is no such thing as a legitimately sick child. Women get abused, and it is awful. Rape is horrific, I know. But just because someone claims to have been abused, it doesn't magically make that person incapable of lying just because the topic is a true thing other people have to face. Heck, good liars always pick stories that sound like real stories.
The problem is that her story has holes SOOOOO big that they show up even when a person who believes her re-tells the story on a message board. That's a red flag. You want it to be true, and that is coloring how you see it. But if you were listening to a buddy tell you this story, you'd be yelling at him that the girl was clearly lying. Maybe she isn't. Maybe she's the poor girl who cried wolf and THIS part of the story is true in spite of her propensity to lie and cheat and manipulate. It's possible, and I don't know for sure. But I'd say the odds are much better that this tall tale is as fabricated as all the rest. Occam's Razor, you know?