courter vs valentine

courter

noun
  • One who courts; one who plays the lover, or solicits in marriage. 

valentine

noun
  • An expression of affection, especially romantic affection, usually in the form of greeting card, gift, or message given the object of one's affection, especially on February 14th. 

  • A person to whom a valentine is given or from whom it is received, especially on February 14th. 

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