Changes in the way you live and questions about your responsibilities. Separating from something important—a person, behavior, emotions—is imminent, has taken place, or is necessary. Compare this to Corpse, Death, Abortion, Sword, Divorce, or Funeral.
Folklore: A good sign, because you are letting go of something.... Little Giant Encyclopedia
Vision: Saving goodbye to others in a dream: take a step back for a while and examine your relationship with them. At the same time, this dream may also be a sign that you will always find new friends. Saying goodbye to your parents: they might be worried or ill. Saying goodbye to a stranger: your problems will soon be over.
Depth Psychology: A goodbye is always a sign of a new beginning. Was it a sad farewell or one that brought relief? From what or from whom would you like to separate at this time?... Dreamers Dictionary