You have my sympathies buddy. There comes a point when a life simply isn't living anymore. Both my parents died within six months of each other this past year. Neither was living the life they would have wanted: Dad had Althzeimer's and mom had congestive heart failure, renal failure, mocular degeneration, etc. I was with them both when they died which was a blessing.

You'll always have the memory of your Grandpa. He really is a part of you, without him, there'd have been no you. He clearly loved you. That's something you can always hold onto.

Whatever your beliefs, his body is gone but his spirit lives on, always. I believe in heaven and a better life to come. He's not in any more pain - he has a knew everlasting body where there is no more sorrow and no more pain - non corporeal. Heaven.

Peace.