It helps me to remember feelings and thoughts are insubstantial. For example bad memories, of which I have loads, are now really only fantasies I make up in my mind, and the bad feelings I get from thinking about them do no one any good.
I've done a lot of stupid, hurtful things, as well as being a victim to a lot of stupid, hurtful things. The past is dead in a very real sense. What is substantial? What you do today, positive things you do to improve things for yourself and others, and they are real, not imaginary mental images.