I can certainly understand the sentimentality, I still cannot butcher my original old laying hens or flock-leading roosters, nor can I butcher my ducks or geese. However, I have become very used to killing & eating the extra cockerels that I've decided are going to be dinner guests right from the start. It was a departure for me at first, deliberately killing an animal for food, one that I wasn't threatened by or disgusted with or afraid of. But now I find it makes me feel empowered to have mastered this essential human survival skill.
Right now I have about 20 young cockerels in a pen ready to come in for dinner. I cannot wait to get them done, they're eating their heads off, making all sorts of noise, and will terrorize the laying hens if I let them out to free-range. They're nice & meaty, it makes our mouths water to feel their fat drumsticks. I'm going to try to do 8-10 of them this Sat, and do the rest in the next week.
It really helps to decide who is going to be meat right from the start, then they are like produce grown in the garden. You can still nurture them while they're young, admire their beauty, take pride in their growth, while anticipating the tasty harvest.