If one anyone saw what happens to a person getting struck by a train, it ain't pretty. Decapitated limbed, severed body, blood and intestines being dragged out for miles. If anyone saw that they'd probably feel extremely wierded out.
Guess who gets to clean all that up? Firemen and police. As a police officer you'll be called to check on old people haven't been heard from in weeks and it isn't a walk in the park. You'll find smelly, decaying bodies that are all bloated and rotting away. Real life can be a bitch like that at times, yet as a police officer, fireman, emt, paramedic, it isn't easy talking about that stuff to your family. To help ease you can sort of joke about it, or talk about it, but there aren't that many people can talk talk to about this stuff. Only your co-workers can understand, your friends and family would be wierded out by that stuff.
If don't do something to ease it, it'll bottle itself up and it becomes nasty baggage. Talk to a cop, fireman, or some emergency responder, you'll find a lot of burnt out people. If don't get rid of that baggage, you'll bun out and every day at work becomes hell.
The people who joke about these things behind a computer skin are just crumbs. They weren't there, they are just using the whole coping thing as a excuse to be edgy.