I rent my house my girlfriend is not in lease. She refuses to leave.what is the best way to proceed to get her out. I'm worried she will destroy stuff

Changed the topic area to Real Estate law. This is not a criminal defense issue.   BUT...give her written notice to leave in a week. Then, contact the police and ask that they assist in supervising her move out. If she won't agree to move after being given notice, you can go forward with eviction...but as to how to do that process, contact a real estate / civil attorney.