let it go vs palliate

let it go

palliate

verb
  • To cover or disguise the seriousness of (a mistake, offence etc.) by excuses and apologies. 

  • To relieve the symptoms of; to ameliorate. 

  • To placate or mollify. 

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