Coming home and finding your wife in bed with a friend is pretty harsh, too.

My ex girlfriend was cheating on me, I found out, but instead of doing the breakup thing and getting mad, I went to her apartment and we had amazing sex. Afterwards I got up and gave her a 20$ bill, told her I could not have sex with her without paying and wish her good luck with her new career as a hooker, seeing as she was whoring herself out to other men.
The look on her face was priceless.