The fact it is a CW surprises me that she'd be acting broody, but that is it. Can I assume you were getting eggs from her in late summer? If you have a place to do it, put her in a wire ottom cage to break her and have water and food available for her in it.
The birds tend to be more thirsty this time of year if they don't have water available all the time. I am not able to have unfrozen water for all my pens at this time and what all of them want most is water when I go out, so that's what they get first.
As for the huge poop, that is part of the broody cycle, when they do get off the nest, they clean themselves out, then go back and set again. Her disposition toward being disturbed goes along with broody sea as well.