Dr. Nicole Cain teaches a visualization technique for unwanted thoughts: imagine your mind as a warehouse of boxes, check each label to see if the thought belongs to you, and return the ones that don't. It helps you identify which thoughts are actually yours versus packages from your past.
Chapters
Here's how to identify the source of unwanted thoughts. Imagine that your mind is a warehouse. In the warehouse of your mind, there are lots and lots of boxes. Each box represents a thought or a belief or a memory that you have as thoughts come up. Imagine going into that warehouse of your mind and grab the box that represents that thought and look at the label. Is that label yours? Does it have your name on it? Or does the label actually say that it's for somebody else? Look at where the label says it's from. Did the label come from somebody in your past that's been an antagonist in your story? Or does it come from somebody valuable and resourceful? Imagine opening the box, exploring the contents, assessing if it feels right for you or if it doesn't feel authentic to who you truly know that you are. If it's not your package, if it's not your box, if it's not your truth, then take out the tape, close it shut, and then stamp it. Return to sender. Imagine taking those boxes that don't belong to you and sending them out of the warehouse of your mind. That is my favorite technique for figuring out what to do with unwanted thoughts.