This is a tough time for you, and your friends. I am sure they love you and feel guilty if they begin to feel they cannot "deal" with your moods/behaviors. You are all also in school and trying to focus on the things you need to do. For you, getting the right medication is a priority. It might, if you can, be good if you could all sit down and talk about this as roomies, maybe there are things you or they can do to decrease the tension around your struggles without feeling guilty. Brainstorm.
You will get through this. And, it is not anyone's fault. (and, who knows, if you weren't bipolar, there could be another, even more difficult(?!) problem...)---my heart goes out to you. Hang in there. [think about what helps you cope, activities that can calm you or cheer you even temporarily; make it okay for a friend to let you know, if you can't see, when you/they might need to do something to ease the tension.] Hope the medication problems are resolved sooner rather than later.