Ugh, having bad neighbors really sucks, i'm sorry. What is her breed? I feel so lucky, my neighbor badgers me to get a Rooster, he WANTS to hear that noise. But he's about 3 acres away from the coop.... And that's the thing, sometimes you need to move to the country to solve the problem of neighbors, period. I got so sick of dealing with all of them that when we looked at our home on 5acres I was worried that it wasn't enough. You can pretty much only hope that they will move, if you don't. Forcing a chicken to be quiet is just not a thing and I'm sure it stresses you out to have to constantly worry about it. Breed dependent, maybe she'll mellow a bit, who knows. My flock of 11 is super noisey.