If I am falsely accused of assault and battery of my husbands exwife...I have (3) witnesses. Can I sue her for falsely accusing me

You can file a civil suit for malicious prosecution in Virginia.  There is no criminal charge for malicious prosecution.  Whether she can be sued will be determined by a number of factors that can be assessed by a civil attorney. This response is general in nature and is not legal advice. No attorney client relationship is formed by it. Further, the response does not represent the opinions or views of LexisNexis or its affiliated companies.