In an extract from his book The Madness Of Grief: A Memoir Of Love And Loss, Richard, said: “It was really, really tough to see somebody you love destroy himself.
“It is like someone is drowning and you throw them a lifebelt but they are just not taking the lifebelt.
“And I did try everything I could think of to help him stop drinking, and in fairness to him he did try too, but it was too much for him.”
Civil partnership
Richard and David had been together for 12 years and were in a a civil partnership.
The couple also lived in a celibate relationship.
Richard often spoke with love for him and their life together, particularly on his Radio 4 show: Saturday Live.