I, too,asked for help on this and everyone said to take her off the nest, remove the nesting material and either put a rubber snake in the nest or put her somewhere else. My Hermione Hen had opted to nest in my potting shed sink, and I took her out last night, shut her in the barn, and closed off the potting shed. This morning, she was still broody on top of a hay bale, but once I opened up the barn and she got into the light, she exploded - CHICKEN RAGE!!!! Whew! She fluffed herself to three times her size, pecked at me, she screamed and yelled outside the shed door, she chased the cat around and under the shed, and flew at the dog and scared the dog out of the yard. She slowed down a little after that, but she refused to eat and kept walking all over grumbling. Finally the rest of her free range crowd showed up about an hour later and she settled down a bit more, started looking for bugs and things, but she sure was a diva for a while there.
Good luck!!!