Your roommate is acting in the capacity of a landlord. You signed a contract and are liable to damages incurred to the contract holder. In this case it would be loss of rent. Unless there is an out in the contract I would say that since the contract is for a month to month period, you would be liable for 990.00 I am assuming that the contract has a 30 day notice stipulation that you would be moving. You may be able to get out of the lease entirely if you can find someone that meets the landlord and the roommates rental criteria. Another approach might be to negotiate a lump sum payment to the roommate and have her sign a release from the contract. Finally, if you can find something in the lease or in the apartment that would make your moving in a hazard to your health, or a possible problem with privacy, such as no doors to your room, then you can fight it in court and possibly win. I would recomment that you negotiate an end to the rental agreement as it would put money in her pocket and she can start looking for another roommate.