Im a permanent resident, my wife comes to visit on a b1/b2 visa, I was told my an H&R tax preparer that I couldn't complete the process without having an ITIN for my wife, she only comes to visit. Does she need one ?

You cannot e-file your return, but you can definitely mail it without an ITIN (assuming you file married filing separately). YOu would write "NRA" in the field for the SSN/ITIN for your wife.
If you want to file jointly, you do need an ITIN for your wife.