If she has authority to rent the premises from the owner it would be binding. From the facts you give, it sounds as though you can terminate by giving 30 days notice. Be sure you have somewhere to go on the 30th day.
Clifford L. Tuttle, Jr.
Attorney at Law
The foregoing answer does not constitute legal advice and does not create a lawyer-client relationship. Answers are based upon the facts stated and may change if there are additional facts not contained in the question.