Guy: I have information that you are cheating on me.
Wife: How do you know this?
Guy: My friend saw you kissing someone. So I hired a PI to find out for sure.
Wife: Your friend should keep his mouth shut. He shouldn't be spying on me. That's the real issue here. You don't trust me. Your hired a PI? How dare you! Nevermind that I'm banging someone else.
Except instead of cheating it was:
Guy: My friend told me he saw you having lunch with another guy.
Wife: Oh yea? It was actually 2 guys. You know that new promotion I got, well my boss and I took our new client out to lunch. I saw your friend when he walked by, my boss had just left the table to take a phone call.
Guy: You're cheating on me you dirty *****, my mother said I should have never married you, the PI I hired said you meet with different guys for lunch every day.
Wife: yea, I'm a regional sales manager, it's kind of part of the job.
Guy: **** you, I want a divorce. Your breath smells like big foots dick.
Wife: you're fvcking retarded.