she should be okay then if she is in the coop with the others ..they will provide some heat for her ..even if she is in her little cage by herself .She lives in a kennel cage within the coop; free ranges when I can supervise.
It's a tough situation. I am considering a friend for her, but it would have to be the right match.
TOB
If you are worried about her ...being cold check her at night after she has been roosting for a while & see if she is cold ..she will probably be warm and toasty .