I was indeed referring to what you dubbed as survival instinct, initially defining it as "what enables a make believe that this dark hour, although certain, is scheduled in the distant future, so far away as to be irrelevant anyway", after which I countered with those, such as the terminally ill, whose dark hour ceases to become so irrelevant as they might be aware of the very real probability of their impending death.
So I asked, and you agreed, that this "instinct" can be shaken.
Then you repeat the claim that it is "so capable of blocking the notion of death so persistently" that "no one needs blind faith".
I do think that circumstances are different. A normal person, a depressed old man, a terminally-ill patient, a warrior left behind in the field to fight, alone, a hundred opponents, a swimmer taken by crazy unpredicatble currents to the open ocean are all different cases, but they are all still alike in the sense that what keeps them ticking is their belief that *their hour* can be (perpetually) postponed. Depending on each individual case, however, such a survival mechanism can just fail at some point.