There is no legal protection against being yelled out, insulted, etc. by another adult--certainly, behavior that includes actual threats of violence, or repeated harassment (e.g. "stalking") may be criminal, but a single incident of being yelled out, even completely unfairly or inappropriately, is not illegal: it is not a crime, and you cannot sue over it. The only thing your girlfriend can do is file a complaint about the behavior with the state medical/dental licensing board, which *may* take some minor action about this.