If we continuously think of what happened yesterday. How can today be any different. If we sit and constantly ponder the negatives, the bad things, and nothing else, how is today going to be any better? We must learn to let go of what negative things happened. Push the thoughts to the side, and as Elsa sings in Frozen, LET IT GO, Let It GO!!!!! You can't continuously think of it. Because in the end all it is going to do is make you sick. So Let It Go so that we can have a better tomorrow and a yesterday that remains at the back of your thoughts because in the end it doesn't really matter.