She is dominant to you. She bit you back cause it works. The first thing that happens is you back off when she bites and in that instant she wins. You actually can't back off. You are gonna have to quit playing rough with her and teach her some manners by being the pack leader. She has to submit to you. I love watching Cesar Milar's Dog whisperer. He has a lot of good advice and techniques on his show. I would try and get with an obedience trainer ASAP if you cannot make progress, they can show you safely how to use the techniques for the behaviors you want. Biting is unacceptable. Playing with her isn't the only way to have a good time with your dog. Walking and giving her a job are actually activities to define your roll as pack leader. G. Sheperds love having jobs and it gives them focus and drive which prevents other bad habits from developing.
