My Hero Has Cancer

You know how you know that the people you love in life are not always going to be in your life, but you don't really think about the fact that they could leave this life ANY TIME? I'm dealing with the fact that my eyes have been opened again to how short life really is and how we must treasure each and every moment we've been given.
My grandfather was diagnosed with cancer last summer. It is in his lungs, but not necessarily what they call lung cancer. He went through chemo and radiation last fall and winter. Then, we waited several months before they could do the tests to see if they had gotten it all. Through all of this, they acted encouraging and like they were going to knock it out, no problem. It was shrinking.
When we got the test results back last week, it was still there. Two spots. One in each lung. My aunt informed me yesterday that the doctor says it's uncurable. This doesn't mean it can't be cured, just that it never has been. She asked him why they were going to make him go through poison again (chemo) if it's uncurable, and the doctor says it is to keep it from spreading.
Grandpa is my hero. He is 86 years old. I know we've had him a lot longer than most people have been blessed to have a grandparent. He is an elder in the church where he has lived in Oklahoma for the last fifty or so years. He's been married to my grandmother for almost 65 years (their anniversary is in June). He is amazing in his capabilities to go out in his garage and make or fix things, out of wood, pvc pipe, glue, nails, metal, etc. He's fixed my car several times and I know he's done the same for pretty much everyone else in our family. He's the father to four kids, four kids-in-law, grandfather to thirteen grandkids, nine grandkids-in-law, and great-grandfather to eleven great-grandkids. None of us have been divorced. Almost all of us are still faithful in our Christianity. I want to be at least half as good a person as he is when I "grow up."
I'm strugging right now. I don't like the thought that there's something inside of him "unfixable." He's who we go to when something needs to be fixed. He helped us buy our first house . . . and sell it. He's just always there when we need him.
He emailed me a while back after I had loaned him a copy of one of my stories so he could read it and asked where he could buy it so he could send copies to his cousins and brag on me. I wish I had been braver and tried harder to get published before now so he could have already done that. Guess I better step up my plans and goals. I wish I could have given him another great-grandchild. I want to go and eat another apple with him, something I used to do when I was growing up. I want to hear him pray again, his deep voice humming up and down as he breathes in and out while speaking. I want to hold his rough, large hands and laugh with him as he teases me.
I know he's not dead yet. But it feels closer than it ever has before. And I'm selfish and not ready to let him go.