A human being has been given an intellect to make choices, and we know there are other food sources that do not require the killing of a creature that would protest being killed.
I live in a kind of controlled awareness. I wouldn't call it fear, but it's an awareness. I know I have a responsibility to behave in a certain way. I'm able to do that.
Take chances, make mistakes. That's how you grow. Pain nourishes your courage. You have to fail in order to practice being brave.