It will take time to tame her. New environment and people have been introduced to her. You need to take care of her more than any other dog. Take her to walk daily. Give her good food and if you could keep some other dogs with her so that she can feel at home.

 I do not know what you do but I do know that the reason that she is not eating because she is homesick and if she is outside you better watch her closely because she will run away and try to find her old owners Your Welcom