HPV Support Group
Human papillomavirus is a diverse group of DNA-based viruses that infect the skin and mucous membranes of humans. More than 100 different human papillomavirus (HPV) types have been characterized. Some HPV types cause benign skin warts, or papillomas, for which the virus family is named. HPVs associated with the development of such "common warts" are transmitted...
I've done research and never heard that this causes diabetes. You shouldn't feel guilty about that, he may have got diabetes for numerous other reasons including diet and health habits or just naturally.
HPV is just a virus and in most healthy people the immune system will lock it down so it doesn't come back. Like the others say try and stay positive and keep faith that you will get over this thing.