go mad vs go to pieces

go mad

verb
  • To become insane. 

  • To reach an excessive or ridiculous level. 

  • To do something extravagant. 

go to pieces

verb
  • To become very upset or emotional, to have a breakdown. 

  • To deteriorate, get much worse, fall apart. 

How often have the words go mad and go to pieces occurred in a corpus of books? (source: Google Ngram Viewer )