Stress can trigger a molt, so maybe, the pictures are not really clear enough to see if there are pin feathers coming in, which would confirm a molt. Do you have a rooster?
Also, if you have a hen go broody and are not going to let her sit on eggs you really should break her, not let it go on, they don't eat or drink well and it takes a lot out of them, so that could be a contributing factor. You can search for how to break a broody hen. How is her weight, check her breast bone to see if it feels prominent, or if the breast is reasonably filled out. I would also give her a thorough going over to check for lice and mites, here is a link with pictures for help identifying them:
http://www.the-chicken-chick.com/2012/08/poultry-lice-and-mites-identification/
With nothing else to go on I would try to up her protein a bit, give some vitamins, like nutri-drench, and see if she starts acting better, molt can also take a lot out of them. Check her crop function (should be full when she goes to roost, and empty in the morning before eating) and see if droppings look normal or not (if not, pictures are helpful) and observe for a while to see if others are feather picking her. If you find anything else let us know. For future posts, if you start a new thread rather than attaching to an already started one you will get more responses. Sometimes when you tack on to the end people may not look as they think it may already be well covered.
