Thanks everyone! Things actually are not going so well. The day I took the picture of her, was the only day I have even seen her. She has since taken to hiding behind the washer and dryer because I guess she discovered she could squeeze back there. I didn't think it was possible for anything to fit there, but apparently a cat can. I haven't had this happen with any of my other cats, so am a bit disappointed. I go into the room every day and leave treats and read to her. I don't know what else I can do, especially if I can't get her out to be petted but there's no hint of her coming out when anyone is in that room. I know she must come out when everyone is sleeping because her food and treats are gone and the litter box is used when I check in the morning. I did email her original cat mom who said that it may take awhile because she was born and lived with her for 4 years, so that's all she has known, so it's certainly an adjustment.
Do cats that take to hiding eventually come out? I can't even reach back there to pull her out, so I don't know what else to do.