This theme is part of what I call the "graveyard of worry". It is like holding a funeral for every false belief that turns out to be false: stopping at it, at the details of what happened when the anxiety came, and writing about them in detail:
"My heart started racing and I thought she had been badly hurt by what I said. But I was completely wrong: she was staring at something else in surprise, and she had not even understood what I said".
As we keep writing about how wrong these moments were, we start to doubt the anxiety the moment it arrives, because we remember well all the times the same pattern of anxiety turned out to be wrong. Little by little you may need to write this way less, and you may start to notice yourself doubting the anxiety as it happens. What this theme focuses on is social anxiety. You can add statements that make clear the relationship between the two people:
"I was worried that I had let S down, and when I met him it turned out my worry was wrong: he had not even noticed. We have been friends for 10 years, and my fear that he might hold something against me has no grounds"
You can also name the reasons for the anxiety, analyse them and put them on trial too, after writing about the day’s event:
"I was anxious about the job interview again. Then I went in, and all my answers were convincing and good, and I got good reactions from the person who interviewed me. The mistake that looks big to me was not big to them. I only worry about interviews because I remember my first job interview, but the truth is that there has not been a single bad interview since".
Or:
"When I heard my friend’s long list of advice, I felt I had failed, and I heard harsh voices that matched neither his tone of voice nor what he was saying and advising me to do. The real reason is that I am still affected by the times my father scolded me when I did not deserve it"