I have a book on my shelves titled, “What To Say When You Talk to Yourself” by Shad Helmstetter. It’s been out for years and may not be available currently, but the theme of the book is life changing. His idea is that everyone talks to themselves all day long every day of their lives. WHAT they say, he says, locks into their subconscious mind and becomes reality. When a child tells him/herself “I am not very smart… I don’t have any friends… I’m a loser” a hundred times a day, it should not be surprising if that child grows up with a very low self-image. But how about if an adult has been saying those things and things like that for 20 or 30 or 40 years? - dozens of times a day, hundreds of times a week, thousands of times a month, ten thousand times a year… It’s not hard to figure out the outcome.
This is not to suggest that we need to lie to ourselves when doing our “self-talk.” But it may be a very good idea to curb the negative things that constantly flow through our minds and replace them with thoughts that are good. One wise person, long ago, suggested that "whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things." (The Bible: Philippians 4:8-9)