While I would not hesitate to pull the trigger to protect my family I would likely have an emotional reaction afterward. As it should be. Only the sociopathic criminals can take a life with out blinking decent God fearing people can recognize something is necessary but still feel sad that the deed had to be done
Yes everyone will have some kind of reaction if they are normal. It varies.
However I tell you it would not bother me that much at all if it’s a clear thief/murderer attacking me or my family. I’d feel good that that person would never harm anyone else where I live, in the town I live in, ever, ever again. That I’d actually done something good for the area I live in. Really would not care about the person’s backstory, or why they were the way they were. None of that crap.