Dont force it. Let the pup learn that you are not going to hurt her. It may take some time but don't give up. Just sit on the floor in the same room with her and let her react at her own pace. Don't try to engage her, just her work herself around you. Also, you may try being the one that feeds her. Don't expect any fast response when you do feed. Just be consistent and let the bond develop between you and her on her schedule.
We adopted our GSD Maddie when she was a year old. She was super shy, withdrawn and fearful. She bonded with me immediately and stuck to me like glue whenever I was home. But it took my wife months to bond with her--Maddie would shrink away, hide and avoid my wife. It took a lot of kind patience before she finally came around. But she did so eventually.
IMHO laying the proper groundwork is important. Here are a couple articles on that subject. Please note that I am just a noob who thinks he might know a few things about dogs but also recognizes his limitations and readily listens to those with more knowledge and experience.
Leerburg Dog Training | The Groundwork to Establishing Pack Structure with Adult Dogs
Leerburg | The Ground Work to becoming Your Puppy's Pack Leader
Best of luck to you and your dog,