Is my friend lying to me *trigger warning*

One of my friends tends to lie a lot. Nobody really trusts her or believes anything that comes out of her mouth because 90% of it is bullshit. She came to me a while ago about a guy that I knew but kinda didn't know raping her. I believed her because who would lie about that. But a lot of what she is saying isn't adding up, and she continues to change her story. First she said she believed he put a date rape drug in her cup of whiskey. Then later she says they weren't drinking. I told her she said he put a date rape drug in her whiskey and she started acting weird and denying she ever said that. She told other friends about it and it seems she told us all different stories. She told one of our friends it happened in his car on this date, told me it happened at a party in a bedroom. Nothing she says is consistent and the amount of times she contradicts herself is ridiculous and if anyone points out she's contradicting herself she gets nervous and turns it on us and makes us look like the bad guy. She sounds like she's made up so many lies she can't keep up with. Also she's telling everybody except the police. She said she doesn't want to ruin his reputation, but is going around telling everyone who will listen, whether they know her well or not. Things aren't adding up, her story continues to change constantly. What she tells one person that happened is completely different then what she tells another. At this point I'm about to be done with her because I'm pretty sure she's lying to me and lying about stuff like that I don't fuck around with.