I can see that an incident like this would affect you and I'm really, really glad I didn't have to see what you had to see, but why should your employer pay out?

I'd guess that they should maybe pay you while you were off sick, but compo? My boss won't pay me if I see a fatality on the road, even if I'm first on the scene and try to help.

Find out who the dead woman is and sue her estate. If anyone is liable for your distress, surely it is her?