Possible Clues:

• 'Don't ___ give up!'
• "Oh, when will they __ learn?": Seeger lyric
• First Lady meeting resistance at all times
• With 43-Down, fairy-tale ending
• For or what ending
• Word following who, what, when or how
• Never have I ___
• Nonstop
• Lived happily ___ after
• Hardly __: rarely