A lot, but I personally knew people who had been forced to learn to write with their right hand as children, with their left hand tied behind the back, because they went to kindergardens or elementary schools with nuns as teachers and they said the left hand is the devil's hand.
I am Catholic and proud of it, but I can see very well why a lot of people criticize the clergy so harshly.
Anyway, what killed a piece of me recently? I'm no sure, maybe realizing that I won't be easily getting the job I wanted because some people called me intelligent. I realized that intelligence is not considered as worth as being someone's friend by many, and that killed a piece of me.