I noticed about two weeks ago that one of my hens was not roosting with the other hens and rooster, she was sleeping in a nesting box. She would go out in the run with the others during the day, then back to the nesting box at night. After observing this for 3 days/nights, I noticed she was starting to be somewhat lethargic. I was very concerned, so I contacted my veterinarian. He determined she had a upper respiratory infection and prescribed antibiotics for 3 days. After 3 days of antibiotics, I noticed some improvement. I noticed when she was laying in the nesting box, the Rhode Island Reds would peck her when they came inside, not let her eat or drink. Then I noticed when she was in the run, she was being bullied by the two hens again (Rhode Island Reds), the following day they were more aggressive when she was in the run. They kept cornering her and pecking her and would not stop until I went in and broke them apart. I have a separate coop and run that I use for a “hospital” when needed. I immediately moved the two bullies to the other coop. She still continued to lay in the nesting box, then she finally went in the run. When I saw her in the run, she had squeezed underneath a homemade nesting box that has four legs. I went into the run and moved the box to free her. She then went inside the coop and into a nesting box. Then other hens came inside the coop, this time Barred Rocks, and they started pecking her while she was in the nesting box. I then decided to move her to the “hospital” coop, and move the reds back to the other coop. She was not moving her wings or head normally and was walking very slow and cautiously. She is by herself in the “hospital” coop and has been for almost a week now. She is out in the run and in the coop, moves freely and is eating and drinking. She is flapping her wings, moving her head, walking normally and grooming again. I let her out separately to free range for a few hours everyday. I am worried she seems fine right now by herself, is much stronger, but I do not want her to get lonely and I do not want to move her back to the other coop with the others and put her through being bullied and injured. Any advice will be greatly appreciated!