Being rear ended on a bike is very very common. Dunno why but I suspect that most cagers look for two stop lights rather than one. It takes them a few seconds more to realise that there is a bike in between them and the vehicle in front. From what you descibe the twat driving the car wouldn't have stopped if it had been a concrete wall in front of them.
Anyway, glad you survived. Don't lose faith. Be a fatalist, if your number's up, it's up, if a cager don't kill ya something else will.
