Someone I Thought Was A Friend Moved In& Turned Out To Be A PSYCHO- How Can I Get Her Out (in NC)?

This WAS a friend-down on her luck so I helped her out. She has been helping pay some of the bills. I asked her to leave two weeks ago and now she won't leave. She says she has a rent receipt from the landlord and is refusing to leave--bcz she's a tenant too. She's acting crazy and smoking a lot of pot in the house (which I am not cool with). I live in North Carolina, PLEASE help!!