Oh my goodness, I am so sorry for your loss! One of the unfortunate things I have discovered about chicken keeping is that everything wants to eat my girls. We had a coyote take one last week and I still feel guilty that I left to run errands and left them out. I understand the distress and guilt you feel! We also had two deaths of beloved girls in our first year, it was so devastating to have happen and we felt so terrible that we could not have prevented their deaths. Time heals, and we soon have good memories of them. We learn from our mistakes. It is really remarkable how special they can become to us. I was very surprised at how much I came to love them all. Right now be kind to yourself, it is clear you loved her so much and that you feel a sense of dedication and responsibility to keep your others safe. I am sorry again, I know it hurts.