I think about having fun, but being careful, riding within my limits and remembering my responsibilities to my wife. It is true we will all go sometime, but, as Kevlar7R says, we can all take protective steps to postpone that day.
Most folks I know that ride have been in accidents of some kind. Almost EVERYONE I know that drives a car has been in an accident, too. It is a dangerous world out there, no matter what you do. Bicycle rider, moto rider, car driver, pilot, etc...
I feel there is a big difference between an accident that I create for myself (riding beyond limits, miscalculation, etc) and those caused by someone else's error (drunk, putting make-up on, cell phone, etc). If I go down due to my mistake, that's riding. Motorcycles are forever at gravity's mercy. Last cager that really scared me by blowing an intersection, I pulled over so I could bitch at her. I yelled and told her how sad, lonely and pissed off my wife would be at her for offing me. I yelled until this woman cried to get my point across and then drove off to change my shorts.
There is dangerous stuff out there at every turn and I think about it. I am not afraid, but aware. Given the choice (whether my fault or others') I would prefer to go doing something I enjoy, just not right now.
A really weird twist to my life is my wife's new interest in mountain climbing. While I consider my riding to be relatively safe, her climbing around avalanche chutes, scrambling up mountain peaks scares the crap out of me.
Trunabout is fair play, I guess. Strange to be on the other side of worry, though.