Negative thinking : worrying about the future, when you are putting your attention to something that hasn’t happened yet.
Negative thinking : re-living something in the past that upsets you, giving juice to a memory that continues to hurt.
As you think about a bad memory again and again you are laying down tracks in your mind. What’s the point in having something upset you time after time?
You can change that way of thinking. I can show you how.
Being conscious of what you are thinking is being in charge of your mind. You can learn how to do this. You can learn how to erase those grooves of habitual negative thoughts.
Read the posts on mindfulness and meditation for help with changing your focus from negative to positive thoughts.