When (exactly) did common courtesy and self-responsibility die and was it murder or suicide?

Based on the thousands of people I have had the displeasure of running into in my lifetime, I know that common courtesy and self-responsibility are dead. I just don't know when and how it happened...lord only knows how many thousands of times I have (personally) tried to reure people that they are still alive, but it's time to accept that they are dead and stop living in a fantasy world...I have a hard time accepting the things I cannot change...but if I had a gravestone or something tangible as evidence to their demise, maybe I can accept it and live with it better...I have become very misanthropic and need to find a way, no matter how silly it sounds, to break away from it before it destroys me...