What is the most heart breaking thing you've ever done?

I'll start this off by saying I'm quite squeamish.

This morning, while I was diving to work I passed a cat that had been hit. From the angle I saw it it was clearly dead, but didn't have any visible injuries.

Knowing that the road was fairly busy, and the cat would likely be run over again before his owners found him I decided that he needed moving off the road. At my next round about I did a U-turn and pulled up on the other side of the road. Approaching from this angle I could see exactly how the cat had died. I grabbed a bag of rags from my car and carefully wrapped what was left of his head and placed him on the grass next to the road (I was on my way to work, and didn't have time to door knock to find the owners).

It really knocked the wind out of me (literally, minor panic attack whilst doing this), but I knew that it would be easier for me to do this that for the owner. Also, it was a stretch of road that children often walk down on their way to school, and no small child needs to see the reality of death in that manner (it really was not a pretty sight, and the full on gore could be seen if you were headed in the direction of the school).

Rigor had set in in the limbs, and there seemed to be a tiny amount of residual heat on the body. In the time from the cat being hit and me stopping to move him no one had thought to do it, even though he was half way out in the lane (a risk to other drivers if nothing else). It saddened me that no one had had the compassion for the owners to move the body out of further danger.