pessimistic (adj.)

• bleak
• blue
• cheerless
• cynical
• dashed
• dejected
• depressed
• despairing
• despondent
• discouraged
• disheartened
• dismal
• dispirited
• down
• downcast
• downhearted
• drooping
• droopy
• forlorn
• gloomy
• glum
• heartless
• hopeless
• hypochondriac
• hypochondriacal
• inauspicious
• joyless
• low
• low-spirited
• melancholy
• negative
• nihilistic
• sad
• spiritless
• subdued
• suicidal
• uncheerful
• unhappy
• woebegone
• world-weary