Why do married men get angry when their wives snoop to find evidence of their cheating?

When in doubt, put yourself in their shoes. There are two good reasons:

  • He's cheating and he's afraid you'll find out who with or knows it's a matter of time before you find out he's actually cheating.
  • He isn't cheating and he's told you he isn't and it hurts him deeply; you think he's a liar; could be overly jealous and insecure and if you aren't content with his answer then the relationship will eventually end.