If you have witnesses who will testify that the your ex-husband and his wife said something about you that was not false and did not constitute an "opinion" and these statements would tend to damage your reputation in the community, you may have grounds to file a civil lawsuit for slander. You would generally need to hire an attorney to file the lawsuit, but you could represent yourself (known as "pro se"). I strongly recommend that you retain an attorney. You should contact the state bar association to see about an 800 number to find lawyers with expertise in the area of defamation/slander torts.
The difficulty you will find is that many witnesses will be reluctant to get involved. And, many lawyers will not take these types of claims on a contingency fee basis.
Here are some links to provide you with additional information:
I wish you the best of luck in resolving this situation.
Slander is an untruthful spoken statement about a person that harms the person's reputation or standing in the community. As but one example, a damaging untruthful spoken statement that you are a criminal might be defamation "per se". Contact a local lawyer - many may give you a free consultation for an hour - to discuss your specifics. Far too many variables exist in the short post you wrote for any further observation by me.
Good luck to you.
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