I call her Jane. There is no special name for a person in that relationship.
Your mother-in-law. Or, call her by her name.
You still call her your mother in law or if you were divorced you would call her your Ex- mother in law.
Well my aunt is what I call my mother's brother's wife meaning we're not blood but that's normally how it works in most cases. Or at least with the first wife because my mother's other brother who remarried after his wife passed & I don't call her my aunt.
You can call her by her first name or if your comfortable some son-in-laws call them mom.
Your mother's brother-in-law is your uncle.
Your mother's brother-in-law is your uncle.
Mother in-law
Taresa is either your mother or mother-in-law. Taresa's daughter is either you or your wife.
The mother of your wife is your mother-in-law.
Your own mother
Well if its Wife or Hansband grandma then its you grandmother in law.
Your mother-in-law.