My name is XXXXX XXXXX I'd be happy to answer your questions today. I'm sorry to hear that this happened.
"Unstable" is typically a matter of opinion. In and of itself, it likely wouldn't be considered actionable. Except in the hands of a licensed psychologist, that is a word that many people throw around, and it carries little weight without anything to back it up. However, if someone is telling people that you threatened them with a gun, that is defamation
of character. Defamation of character is an untrue statement of fact, made to a third party, that tends to harm the reputation of the person about whom the statement was made. When the statement is about the commission of a crime, reputational harm is presumed. Thus, you may have a claim for damages against the person who made the statement.
The administrator unfortunately isn't responsible for this other person's actions, unless she is repeating the statements or telling other people that they are true. Under federal law, the owner of a website or person who hosts a forum is not liable for comments made by third parties on the site.
Typically, these cases are brought in Small Claims
Court. If you are able to tell me where you are located, I can get you more information about the Small Claims Courts in your area.
Please rate my service positively before signing out, as this is the only way that I get credit for the time I spend helping you. I hope that you are 100% satisfied - otherwise, please reply so we can continue the conversation. Good luck.