The moment of near despair is quite often the moment that precedes courage rather than resignation. In a sense, with the back to the wall and no exit but death or acceptance, the options narrow to one.
Perfectionists and zealots can break but not bend; in my experience they are subject to burnout from diminishing returns or else, to borrow Santayana's definition of the fanatic, they redouble their efforts just when they have lost sight of their ends.
For those facing a long haul and a series of defeats, pessimism can be an ally. Apart from anything else, as some Native Americans have also discovered, the presentation of the bleakest and starkest possible picture can have the paradoxical effect of mobilizing the emotions and intellect.