I had 2 of my Buff Orpingtons go terribly broody on me, and it was very stressful for me and them! The one, I was certain she would starve to death, and in fact on my Yahoo henpecked group several people said it can happen. My one went broody for much longer than would have taken to incubate eggs, it was weeks. I work every day but would take her out of the box every time I was home, and I would put ice cubes under her in the box (didn't work) and I would also dunk them in cool water every day, and that at least got them out of their hormone trances for a little bit. I did feed them on the boxes, they both took snacks but they still lost a lot of weight, and still are the smallest in the flock. These girls sat on empty nests, it didn't matter whether or not eggs were in, of course they preferred eggs. The only thing that "broke" them in both cases (girls went broody at 2 separate times, incidentally, right after I got wooden eggs to get them to lay in more than one of the nesting boxes) was to #1 "break them up" whenever I found them on the nest, meaning get them out of there and make them get outside with the rest of the flock (even though they'll just growl at them) and #2 at night, move the broody one into an elevated position, I put my girls on a milk crate INSIDE a large wire dog cage so they couldn't get warmth under them and couldn't get back to the nesting box. Then let them out with the rest in the morning. I can fit the dog crate inside the secure chicken run, so they were safe. In both cases it took 3 nights but it was an absolute cure. I wish you luck and hope this helps!