The sad truth is, we're a lot more fragile than we want to admit, more easily damaged, more easily bruised and broken. We survive, and we heal, but only just, and not always well. Our wounds run deeper than we realize and our scars don't always fade. Such odd, malleable, destructible creatures we are. I sometimes frankly can't blame people who want to believe themselves of another species, even if only on the inside; we humans are so desperately capable of damaging and being damaged.
Gloomy thoughts, I know, but some days you feel the ache of ancient injuries, the twinge of wounds improperly healed, the tug of scar tissue that can never flex and bend as it did before the hurt ever reshaped it. It's hard for me to believe in intangible things like souls, but I'm able to believe in them metaphorically, and I'm able to believe that souls can be metaphorically crushed, as hearts can be metaphorically broken. The pain, and the effects, are anything but metaphorical.