helpmate vs wifeling

helpmate

noun
  • A wife or spouse. 

  • A person who supplies help or companionship. 

  • A recreational problem in chess in which both sides cooperate to achieve a specific goal. 

wifeling

noun
  • A wife; a little wife. 

How often have the words helpmate and wifeling occurred in a corpus of books? (source: Google Ngram Viewer )