regretful vs repining

regretful

adj
  • Full of feelings of regret, indulging in regrets. 

  • Sorrowful about what has been lost or done. 

repining

noun
  • The act of fretting or feeling discontent or of murmuring. 

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