I'm sorry to hear that.
My grandfather was a very serious alcoholic (and chain smoker, too), and he didn't even reach the point of admitting he's an addict, he lived his whole life like that- and eventually died in 1990 (at the age of 54).
My father hated him very much (he wasn't the silent type of alcoholic, my grandma and him quarreled a lot, once he chased them around the garden with a hatchet), and my father witnessed all of that.
When he died in 1990, all that anger and hatred turned into guilt and sorrow; that's when he started drinking as a way of suppressing/escaping reality.
In my opinion, he's already a lost case and cannot be saved. He's been to countless hospitals, "consumed" like 15 psychiatrists, went through a horrific amount of anti-depressants, there were some progress, but eventually he always falls back into the pit.
And I'm tired of seeing this again and again.