When I was little, I was afraid of the dark, and I didn’t understand why it made me nervous. So, I invented monsters that lived in the dark. 

Why did that help? 

Because I decided that making scary faces at the dark would scare the monsters away, and turning on a light would make them evaporate. 

Make up thing to explain irrational fear > make up method of banishing thing > brain is satisfied > no more fear.