I will follow you into the dark

As many of you know, I will follow you into the dark is a song by Deathcab for Cutie, a band which I saw in concert last night. One of my favorite songs by them is I will follow you into the dark. At first, it sounded the lyrics sounded weird, almost suicidal. But then my father rand brother explained to me that it is not about guy who will kill himself, but rather someone who is dying at the same time as his wife, and wants t be when her when she dies.
I saw the music video a few minutes ago, and I liked it. It showed the lead singer living his daily life while there was a hole in his one room apartment that was growing larger and larger, until he finally falls in. The end he is standing in the hole with just the top of his head sticking out from the pit, and he walks in through the hole to somewhere else.
I assume the hole represents a cause of death, like a growing disease, which eventually consumes him. The thing that struck me as odd is that he didn't try to pull himself out, he just walked on through to the afterlife.
When I asked my brother about this, he said that he simply wouldn't be able to pull himself back up, but I'm not so sure. I think they made the hole purposely within reach of his escape, but he chose  not to. Why?
I think it is best t this point to quote J.K. Rowleing from her 6th book (Quote approximated): "People do not fear death, but the unknown."
Dumbldore said that, and as most know, he is about 150 years old. I can link this back to a quote from my mom "sometimes old people who know they re about to die re fine with it. They don't fight it. It is their time."
Since I am young, I can't imagine being just "Ready to go". If I were dying of cancer or something, I would cry and scream and be miserable the last days of my life. what if there is no afterlife? What if I just go out, like a candle?
But nevertheless, some old people feel lie it is their time to go, no matter what  the end brings. Besides, people who have died and then had their heart re-started say that, while dead, they were still expeirienceing something. I wonder what it would fell like.