My roommate and I are on month to month. I want to leave at the end of May when we graduate. She wants to stay until August. She wants me to keep paying rent until then - obviously we are not currently getting along. The landlord has said that I need to get her signature on my notice to vacate or he will keep me on the lease. Roommate refuses to sign. Nothing in my lease said anything about having my roommate's approval before I leave. What to do please?