Thanks for posting this thread. I would like to know the answer myself. I also work with someone who seemingly wants to be my best friend one day and the next day will turn around, degrade you and stab you in the back. It doesn't sound normal to me at all. This cycle keeps repeating itself and drives me crazy. Help! Does anyone out there have any explanations for such behavior? Or, how to deal with it?

Is she just being nice to you to avoid a complaint being filed with the company?