cross to bear vs nightmare

cross to bear

noun
  • A problem, or unpleasant or painful situation or person that you have to accept and deal with, although you find it very difficult, or it causes trouble or worry for you over a long period of time. 

nightmare

noun
  • Any bad, miserable, difficult or terrifying situation or experience that arouses anxiety, terror, agony or great displeasure. 

  • A very bad or frightening dream. 

  • A feeling of extreme anxiety or suffocation experienced during sleep; Sleep paralysis. 

verb
  • To have a nightmare. 

How often have the words cross to bear and nightmare occurred in a corpus of books? (source: Google Ngram Viewer )