commiserate vs rub it in

commiserate

verb
  • To offer condolences jointly with; express sympathy with. 

  • To sympathize; condole. 

  • To feel or express compassion or sympathy for (someone or something). 

rub it in

verb
  • To add insult to injury; to emphasize one's strengths or another's weaknesses in a manner that degrades another. 

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