A protective order is the not the same as a crime. The court order is there because someone could commit the crime, so he is ordered to stay away so that he doesn't. There is by and large a low burden of proof to obtain a restraining order because the inconvenience to the restrained person is so low as compared to the increased safety of the victim. HOWEVER, the right to possess a firearm is a very important right; the removal of which ought to require the actual commitment of a crime as opposed to someone accusing the possibility of a crime being committed. Keep in mind that the Supreme Court holds freedom of speech in the same echelon as the right to bear arms since McDonald v. Chicago. In addition, the vast majority of firearms are unregistered in the United States, making the police seizing a gun owner's property an impossibility in most cases.
Like it or not, as long as gun ownership remains a fundamental right in the USA, the best thing for someone filing a restraining order against a gun owner is to buy a gun herself.