I am a tenant in Philadelphia, PA with a year-long lease term with two other people who's names are also on the lease. One roommate ended her lease prematurely, but she had been living there for 2+ years and was on a month-to-month lease. The reason she ended her lease prematurely was because our other roommate is mentally unstable, and a nightmare to live with. I don't begrudge her for having a psychological disorder, but I do begrudge her for (making the mistake of) disclosing to me that she often forgets her medication, or doesn't take it when she feels artistically blocked (she's a 19 year old art student). This has been the cause of almost every altercation. She's also on probation at school for having episodes on school property, and faces being expelled if the school finds out she's not medicating properly. The roommate who left prematurely picked both of us to live with her at the same time, and at the time I didn't have a choice in the matter. The replacement roommate and I are also having a hard time dealing with her, and our ability to "peaceably and quietly have, hold, and enjoy the House for the Term" (straight from the terms of the lease) continues to be a nightmare. Can I terminate the lease based on this breach of the lease? Ideally we'd like her to move out, but are both willing to find a 2BR and leave her behind. I talked to our landlord, who asked us if we felt the situation was unable to be resolved, and I said yes, but then she responded by saying that it is beyond her responsibility as a landlord. The lease says that if I terminate my lease, "rent and added rent for the unexpired Term becomes due and payable at once." What are my rights and options as a tenant given the circumstances?