That borderline/bipolar diagnosis boundary can be a *bitch*; you don't know how much I feel for you based on some experiences of my own.
Given that her meds previously seemed to stabilize her until she had the allergic reaction ... my total nonprofessional advice would tend toward giving her as much time to stabilize on this med as you can stand. (I don't mean acting a-ok with OM or anything; she absolutely will have to deal with that herself at some point. Just not actively pushing her toward any major decision *at the moment*.) You're the only one who knows how much you can take.
Are you doing everything you can in the direction of self-care? Good nutrition/sleep/exercise? Like you said, taking care of yourself IS work. Don't underestimate the benefits of good physical maintenance on your mental/emotional state.
((((Tristan))))
"Show me a completely smooth operation and I'll show you someone who's covering mistakes. Real boats rock." -- Frank Herbert