As an empathic person generally someone actually dying on video, or in front of me is really disturbing. I used to work in a hotel casino and one night I saw someone jump from a 6 or 7 story tall parking structure one night. That was both really shook me up, and made me really sad for that person, having had their life come to that.
But context is everything. For example: Seeing someone brutally murdered, or commit suicide shakes me on a very deep level. Seeing someone attempt to attack someone else and get killed by the person they're attacking doesn't bother me nearly as much. To the extent that I live in a no bar to carry state, with open carry laws, so I cherish self defence, even if it costs a criminal their lives. This might sound callous, but if you're going to threaten someones life, I won't feel sorry for you if that someone takes your life to defend theirs. I might feel sympathy for the family of the criminal, but I also understand that the right of a law abiding citizen to defend them selves. To that thought if you're gonna cause serious injury, or death to someone in a criminal act, you're forfeiting your life by wilfully endangering someone else.
As per-context, if someone loses their life doing terrible things like the ISIS jerks do, then I'm a lot less affected by it. These people are monsters and they should die. Maiming women, murdering people left and right, forcing children to fight as soldiers, raping, pillaging and more. Each ISIS fighter who dies is doing the world a favour.
If someone dies doing something incredibly stupid and I see it I'll be affected to an extent, but still realize it was their own damn fault. If I didn't see it I'll probably think it was funny, Darwin Award territory you know.