Possible Clues:

• Eeyore, for one
• One who identifies with the answers to the starred Down clues
• One girl about to be grabbed by unwanted person expects the worst
• Person who expects the worst
• Drill on ship I failed, say. A no-hoper?
• Glass-half-empty type
• Half-empty-glass person
• Times sips, perhaps, as one who sees glass half empty
• The glass is always half-empty for this type
• Glass-half-empty person