What an incredible man.
Let me remind you - his daughter, Helen Meads, was killed by husband Greg Meads over a marriage breakup that went sour.
David and his wife were thrust into the role of grandparents as parents and David went on his tour of the country talking about family violence.
He's now written me the most moving and incredible letter, let me read you some of it:
"I suppose I was rather shortsighted to think I could do the trip and come on The AM Show twice and the world would pass me by.
"I don't know how you rate your work, or how you understand the effect of your broadcast on your audience, but I have been inundated with requests.
"I guess, Duncan, I am saying thank you. You have helped me and helped lots of people. It has opened so many doors.
I now spend all day working for culture change in our communities.
"It's about lifting the bar.
"On a personal note," David wrote, and here's where he got me, "you mentioned how well you got on with your dad and how much you miss him. That touched me and gives me great hope for your boy, Buster.
"You see, your dad gave you all you need to raise your boy. He gave you time. This is the greatest gift. Don't stress about being separated and his relationship with his mum, that's their thing.
"These are just my thoughts when they're not asked for, but people just need to keep talking.
"Problems emerge when they stop.
"Thanks again, you have supported me superbly. You stand tall in my world."
It's honestly the nicest, kindest letter I have ever received. And I don't read it to you so you can hear the wonderful things he said about me, I read it to you so you can understand the power of this man, the value of his encouragement, and the strength of human kindness.
Thanks, David - I have the deepest regard and respect for you.