I tend to view Wilson at this point as being in a similar place to a rather infamous mountaineering incident (which was filmed in "Touching The Void") in which two guys are coming down a mountain. One falls. His buddy is still roped to him, and he's holding the guy up as he hangs in midair. But he keeps slipping forward, the weight of the first guy dragging them both down. After an hour or more, he has no choice. He doesn't know if his friend is alive or dead, but knows that if he doesn't cut the rope, they'll both die. He cuts the rope, because he's tried everything else and it's the only way he can survive. That's Wilson. That's where the image of the cliff came from that I used in the story. He can't win, but he knows that if he doesn't do something, he'll definitely lose.