To make a case for defamation, you will need to prove that the statements being made by another person about you are untrue, and that you have been damaged by those statements. Obtain a verification from someone that your soon-to-be ex mother in law made the statements to. However, without damages, it is probably not worth pursuing. You might want to consider telling your parents and your neighbors that your soon-to-be-ex mother in law is not telling the truth, and is simply trying to hurt you because your marriage is over. If that's not enough, then locate an experienced trial attorney who has handled defamation cases and discuss the case with that attorney. In most states, defamation cases have a short (typically one year) statute of limitations.
You have to prove that your were actually damaged by her statements, either by someone else believing them and/or financial loss. In the emotions of a divorce, lots of crazy stuff is said by a lot of people. Most third parties understand all that and take everything they hear with a grain of salt. If you feel the need to refute her statements to your parents and neighbors, then do so. I would think, though, they'd all know you enough to determine what is true and what isn't. This is not going to be worth your trouble. Focus on the divorce, getting the kids thru the divorce OK, if there are kids, and moving on with your life.
To questioners from West Virginia & New York: Although I am licensed to practice in your state, I practice on a day-to-day basis in Massachusetts. I answer questions in your state in areas of the law in which I practice, and in which I feel comfortable trying to offer you assistance based on my knowledge of specific statutes in your state and/or general principles applicable in all states. It is always best, however, to work with attorneys and court personnel in your own area to deal with specific problems and factual situations.
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