Ransac: Condolences to you and your brother.
I've lost two grandmothers in under two years, but both were 90+ years old and very sick. No, expecting it doesn't make it any easier, but sometimes I'm comforted by the thought that their passing isn't necessarily what's best for the rest of us, but it is what's best for them. I suppose it depends on your religious beliefs, but to me, death is a better alternative to a life spent in unreconcilable pain.
So reflect upon the good times and celebrate the impact your grandfather had on you during his time spent on earth. For when we are remembered, we can never truly die.