The bully does not say goodbye

That's right.  Often when I leave the office and say 'bye everyone', everyone but the bully responds.  She pretends not to hear it and looks down on her keyboard, but behaves completely differently when another team member leaves.  The same applies to 'saying good morning' - everyone but me gets one.  Occasionally, she does acknowledge and I cannot help but think this is because her boss is in the office that day.  So, I lowered my expectations of my boss and and it is no longer my issue but her's.