Do you have a written lease with this person? Is she paying monthly rentals? If this is a landlord and tenant relationship, give her written notice to vacate the premises. Thereafter, file an eviction complaint with the local District Justice to remove her from the premises. If she is entering areas of your home without permission, call the local police and have them speak to her. Review this matter with an attorney before taking action against this person.
You should contact your own attorney before deciding on a course of action.