> Your conclusion shouldn't be that seatbelts don't do much
My conclusion is weaker than that. It's that while we try to do what we can, we should retain a kind of humility and realism, that we remember we don't get a 'final say' over own fates. And also that we recognize our continuity with the disabled, even in times of our own health, and that our individual pursuits of health not become a desperate striving to separate ourselves from others who are perceived as weak or helpless.
I think one of the things that has made my father's predicament so earth-shattering to him, beyond even the prospect of death, is that he really wants to think of him self as the kind of person who 'doesn't get sick', that he could really, simply, choose to be well. As a result, the cancer has been not just terrifying and uncomfortable, but an irreconcilable challenge to his worldview. As a result, it seems like he's really struggling to integrate an understanding of his current situation into his perspective. Instead, he flips back and forth between his old view (that he's kind of invincible, that disability and illness are for other people) and a new despair.
Remembering the limits of our control isn't, for me, about giving up, but about grounding ourselves and staying connected to others (including to those who are ill or disabled in ways we might not want to even imagine as possibilities in our own futures).