A fundamental rule of defamation law is that truth is an absolute defense. If the alleged statement is true, the publisher cannot be sued for defamation or slander. Finally, communications between married couples are not subject to defamation lawsuits. The truth is an absolute defense against a defamation lawsuit.
But keep in mind that proving the truth can be difficult and expensive. A private figure who reports defamation to your neighbor, your roommate, or the guy who walks his dog to your favorite coffee shop just has to show that you acted negligently, that is, that a reasonable person would not have published the defamatory statement. The United States Supreme Court has said that, in the context of defamation law, the rights of institutional media are neither greater nor less than those of other individuals and organizations that participate in the same activities. If a qualifying privilege applies to a statement, it means that the person suing for defamation must demonstrate that the person who made the defamatory statement acted intentionally, recklessly, or with malice, hatred, resentment, ill-will, or resentment, depending on the law of their state.
State common law and statutory law govern defamation actions, and each state varies in its standards of defamation and potential harm. For more information on defamation, see this article from the Florida State University Law Journal, this article from the Valparaíso University Law Review, and this Harvard Law article. A tort simply means a wrongful act or omission that causes a personal injury and gives rise to a civil liability claim. In a defamation lawsuit, the jury will be instructed to examine all the circumstances surrounding the issuance of the defamatory statement, including how well they knew the defamed person, how well they knew the person to whom they made the allegedly defamatory statement, how accurate the allegedly defamatory statement was, and why they made that statement.