you can sue for liable. I don't think it is a good idea unless the lady disparaging you: 1) went way over board and 2) is wealthy. Hate to see ytou win but never collect. Tough cases because the damages are hard to prove.
You can create some web content so that people who search your name will not see the negative review.
For example, if you create a LinkedIn profile this site will most likely rank #1 for your name.
You should also respond to the negative review by posting your side of the story.
Defamation on the Internet is tricky thing to establish in court. Truth is often a defense. Then there's the matter is demonstrating that the hurtful speech were fact statements and not mere opinions. Generally speaking, the First Amendment to the United States Constitution insures free expression. Slander liability varies by state.
With the Internet, it may be difficult to predict where suit can be brought or what law applies. Consult a lawyer in your jurisdiction familiar with libel and slander and media law issues.
Even if defamation can be established as a matter of law (liability) a determination will need to be made whether sufficient monetary damages can be established and collected.
Putting your side of the story online to rebut the negative posts may be a strategy worth considering.
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