Kate, is there any way you can contact this so called friend of your son? If you could visit him and give him your piece of mind face to face, maybe you can convince him never ever to call your son again. Wish there was an island where you could plant your son in the middle of it. He would have to live there for at least three years, and be bombarded with healthy foods, healthy motivating talks, and experience a rebirth.
Whatever. Dear Kate....you have done all you can do. It's good that you are ready to let go. Yes, let go and concentrate on your two other children.