I'm an intern at a small law firm and I'm having trouble dealing with people.

This woman is fucking insane. I swear. For some reason she doesn't like me, which I could give two shits about, except now she's trying to sabotage me at every given opportunity, with PERFECT plausible deniability. It's always small, subtle things that make me look just a little worse than before. She'll go into my word documents and change words so that they're misspelled. She'll talk shit about me being on my phone when I'm not on my phone. She left her dirty coffee cup on my desk and then told everyone that I'm a slob.

Once she gave me a project to do. I did it completely and perfectly. A few months later she told me that I did it incorrectly and showed me a few lines that I had supposedly forgotten. I took me a few moments to realize that it was a COMPLETELY DIFFERENT PAGE than the one that I had done. Since I'm an intern, I'm given small easy tasks and she's TRYING to make me look incompetent.

So far my defense is to try to do everything 100% perfectly but the stress if fucking killing me. I'm constantly paranoid about what she'll do next.

Thinking back to my past jobs, I think that I might have experienced this before I was RP-aware.

Who the fuck does that? How bat-shit crazy do you have to be to gaslight some random dude at work like this? Is this even common?