Most Helpful Girl
I can imagine it being so difficult for you. I'd find that painful. The only thing you can do is try to just be civil with her, and put on a fake smile until you find another job.
Sometimes you have to hide how you really feel behind a fake smile. Even though it's killing you inside
Most Helpful Guy
Just be polite. Ignore everything else. And yes, time to move on - either one of you, but working together is to work in frustration and hurt.