Possible Clues:

• Absent young woman at home? Good
• Absent maiden is sitting on grass
• Absent with location unknown
• Girl can't sing properly round church, as several lights are here
• Longing to see
• Not where it's expected to be
• Like the letter O in this puzzle's entire solution
• Lost ... or, in two words, an apt description of 17-, 24-, 47- and 59-Across
• Lost, according to this theme
• ABSent