Sorry to hear about the passing of your wife, Phizzy.
I think that people, by and large, want to get along. We're social creatures, after all. In the right environment, we are friendly and caring and giving. In the wrong environment, we become defensive and selfish. I am glad that I moved from a crowded city to a more rural area nine years ago. I drove 650 miles away, but it's an entirely different world, it seems.
Unfortunately, getting to a position of power means becoming a more aggressive, assertive, and selfish person. You won't survive otherwise. And, once at the top, you are faced with a multitude of people seeking to get where you are, which usually means pushing you off the summit. The traits required to become the leader of a large nation are some of the worst traits for actually leading people. I think they world will be like this for a very long time; problems at the macro level, human kindness and cooperation at the micro.