I would write to her husband with the basic details of your identity, age, former name, schools etc and state that you are not who she thinks you are and that you will be involving the police and taking legal action if she continues to abuse you and spread malicious rumours. Just be factual.
I say write to the husband, because then he will be aware of it and she won't be able to hide your contact from him.
Do keep a record of all contact and start with the beginning. If the police treat it seriously as harassment (I think it has to be at least 2 incidents) then they may go round and have a word with her and put her straight.
If I were you I would also talk to as many friends as you can and advise them what this woman is doing and ask them to shut her down each and every time she mentions you.
I have had a group of women spread malicious rumours about me, ganging up on me, being aggressive to my face and it is not nice. I avoid those people now, and put anyone straight who repeats the lies.
If she wants to continue to live in your village and get on with everyone, she needs to apologise to you for getting it wrong and put everything straight with anyone that she has spread garbage to.