I tend to spend a lot of time on my character creation with adding fluff, so I do tend to get attached to my character, but if they die, that means I get to make a new character (which is something I love doing anyways).
But I've been playing off and on since 3rd Edition, and I've only had two die. One I was disarming a bomb and rolled 13 1's, and the other sacrificed himself for the team.
And as a GM, I've killed 3, and forced one into retirement (mage gone burnt out), and out of the 3 deaths, 2 were due to players doing really dumb things, and the 3rd was the team just had some really bad rolls, and tried pushing their luck too far anyways.