In the letter, Mathis recounts when he learned his daughter, a high school senior at the time, was gay.
“I confronted Patti and I said some things to her that still eat on me to this day. I told her I was sorry that I said those mean things to her."
After his daughter killed herself in 1995, Mathis wrote that he stopped attending church as often, as he couldn't stand sitting through an anti-gay sermon.
"I was ashamed of myself for sitting there and not defending Patti. I have not been much since."