You could pursue a slander lawsuit, but that's not what's going to build trust back into your marriage. For one thing, the lawsuit will bring attention to this lie. You will have to prove, somehow, that what the woman said was a lie. It will cost money. Any, after all that, you could still easily lose - and people will have a reinforced view that you were, in fact, having an affair. Best to focus energies on improving the relationship with the wife.
First, liber and slander are subject to only a 6 (six) month statute of limitations in Tennessee. I would recommend counseling and developing scenarios and situations where you wife would be more likely to trust you. However, if you really want to sue in this scenario, you certainly can (subject to the short 6 month statute of limitations). Keep in mind that this will be an expensive and drawn out process that will divert much of your energy away from your marriage and towards this lawsuit. Even if you can prove that the wrongdoer lied, the damages in your case are difficult to evaluate by a jury. --Certainly you have been harmed, however, is it worth 5,000, 10,000, or 250,000? It is impossible to say and this is different for everyone. Often a case like this can cost $10,000 to get to trial and can take a couple of years to get to this point. Even if you win and a jury comes back with an award of $10,000, it is likely that you will have spent or accrued debt to a lawyer in an amount very close to this through the litigation process. Therefore, your recovery may be minimal, but the cost of time and emotion in pursing this course of action will likely be high to both you and your family. Good luck.
Defamation laws or slander and libel laws vary by state. But, generally, to be slander or libel, someone must make a negative, false statement of fact about a person to a third party that causes harm.
You need to seek to hire a lawyer in your locale, because without a lot more detail, no further observation is possible.
Good luck to you. You should consult with a local TN attorney to determine your rights and the best remedy for your situation.
You might find helpful my Legal Guide, "Successful Start for a Personal Injury Lawsuit"
You might find my Legal Guide helpful "How to Choose A Lawyer For You"
You might find my Legal Guide helpful " What Do I Tell My Lawyer"
God bless you.
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