A good start would be a dictionary of the American language.
The dictionary will tell you that “pet peeve” stands without the hyphen.
Of course the dictionary won’t say anything about not using the hyphen the first time around, but then using it the second time around, nor will any of the stacks of stylebooks you have there on your desk.
Such reference books tend to deal in clarity and correctness, not randomness and ignorance.
All in all not a bad question, gunner. I think we are finally making progress.
You can cite me on that.
Ok, so you don’t have an answer. Got-it. (I added the hyphen to piss you off).