Think about nothing but how you did exactly what you should have under pressure, and how brave you were to just not run inside and start freaking out. Think about how the kids life was good, not that he died. Think of how bad the truck driver must feel, and not of him as a heartless Ass. Thats really the only reason your freaking out, the fact that now you think that there is a rampaging murderer. He didnt mean to, and once you fully realise that, you can accept the entire situation.