zugzwang - you did the only thing you could do in that situation, don't blame yourself for what happened.
I remember a train I was on running over a sheep once - it almost derailed us (our trains are very light and only 2-3 carriages long!). That was bad enough. My dad used to work on the railways, walking along the tracks repairing sleeprs etc. He said it was a bonus when they found rabbits and hares that had been hit by trains - they'd get hot rabbit stew for dinner (lunch!!) on those days! I can almost picture those guys sat trackside, tucking into hot stew! When they found a sheep, there was a cafe which used to buy them - they couldn't do that these days of course with all the regulations!!
Tigerman:
No, you're weird because of your vivid description of you running over the deer . . .it almost seems like you enjoyed it.
I'd disagree with your comment. What zugzwang is doing is classic post-trauma reaction. You literally relive every millisecond of what's happened and it replays in your head until you can begin to make some sense of what happened - 'what if I'd done this? ..not done that?' etc. It's very therapeutic to write it down somewhere.