Antonyms of hopeful:
hopeless, heartsick, insoluble, helpless, inauspicious, futureless, forlorn, lost, bleak, despondent, black, despairing, unhopeful, unfortunate, dim, desperate, abject, cheerless, comfortless, doubtful, dubious, uncertain, bearish, grim, negative, unfavorable, funereal, glum, gray, miserable, wretched, dark, depressing, discouraging, disheartening, dismal, downbeat, dreary, gloomy, pessimistic, unencouraging, unlikely, unpromising, unpropitious, unhappy, unlucky, calamitous, catastrophic, disastrous, fatal, ruinous, baleful, dire, direful, doomy, foreboding, ill, ill-boding, menacing, minatory, ominous, portentous, sinister, threatening.
Examples of usage:
  1. It makes one feel young and hopeful- jolly; doesn't it?
    "A Prisoner in Fairyland", Algernon Blackwood.
  2. " Something may have happened to delay him," said the manager in tones that showed he did not believe his own hopeful words.
    "Jimmy Kirkland and the Plot for a Pennant", Hugh S. Fullerton.
  3. The rest depends upon you, and you alone, and I am not very hopeful about it.
    "The Great Impersonation", E. Phillips Oppenheim.