Legal Question in Real Estate Law in California

No, of course not; if you are both on the rental agreement, presumably as co-tenants, she cannot demand that you leave any more than you can demand that she leave. Now, that said, as a practical matter you and she need to decide whether she moves out, you move out, both of you move out (after giving appropriate notice, of course) or you co-exist for a while longer even though not the best of friends.