My work has inter-office instant messaging, and after I got off a call with my boss, I messaged my best friend that our boss is a retard bitch.

Yep, you guessed it. My boss was standing behind her. She saw it.

She hasn't said anything to me yet, but I'm terrified now. I don't know whether to say something first, or let her say something, or just pretend it didn't happen.

In my defense, my boss was being a retarded bitch that day.