Give it up

Why do we dwell on things in the past? We made our choices and now we have to accept the consequences. Why do we question things that we chose? Why do we wonder what things would be like if we chose differently? Or did something that we did not? I've been asking these a lot lately. I've been wondering if the choice I made to make myself happy was the wrong one. I like to make others happy yet I chose something that made a lot of people very unhappy. And they like to make sure I know it. But why? We are all just thinking of what could have been instead of what is.