Yes, I have, on many occasions.
I have hurt girls during my adolescence because of my mentality of 'consume and throw away'; I have hurt my mom too with my stubborn and rebellious behavior.
The person I have hurt the most, though, is my best friend from high school times.
We lived about 900 km away from each other, and I would stay at her place for a week every odd month or so, except during vacations where I would stay two weeks.
Her parents were very welcoming and always very polite to me.
She was overweight, and she constantly needed someone's attention to make her feel as an attractive girl. She had the same boyfriend for many years, and probably still has. One summer we planned to meet in a city and go to a concert; there, she met with a guy younger than her, and quickly got in his bed. I was extremely disappointed, and had to reveal what she had done to her parents and boyfriend ( who deserved to know the truth, they are the best parents I ever met, and the boyfriend himself was a saint ).
Our friendship ended just like that, she trusted me with everything, I betrayed her and she never forgave me.