I know I am repeating what others have said in the last few posts, but that is okay. I will forgive myself.
Killing a layer is different because even if we plan on killing them "someday" when they stop laying, we do not expect to have to do it soon. We are simply not mentally prepared.
In the past, I have been around to help process my boys. I knew getting into chickens that I would have to accept it. Fisherlady took a few boys throughout the last few years when I was alone, and did not know how to clean the meat (I could break a neck and pluck). When a hen had to be put down, she was buried. My husband could not handle cleaning a "pet". A month ago, a hen broke her leg and was being pecked to death. Thankfully, someone was here that was able to process her for me. I was not "ready" for her to go, and only was able to help pluck a few feathers. It was very hard.
Now that I know how to do everything myself (I am still not a pro, but I can get it done!

) I am sure that the next time a hen needs put down, I am going to have to process her. She doesn't deserve to have her life wasted by becoming food for animals and creepy crawly things. I know it will stink having to do it. I know I will not be ready for her to die at my hands. But I will use the unpreparedness to my advantage. I will do it quick before I have time to think, and if it starts to bother me later, she can go in the freezer or to someone else.