False implications by in laws

I have been married for 2 years (arranged marriage) . We initially had few hiccups in the first year, in the period of adjustments with in laws. But within 6 months my mother in law started accusing me of stealing household things like her clothes, stuff from the kitchen; claiming that all is being done to mentally torture her. When the situation become unbearable, my husband decided to shift on a different floor in the same house, with separate kitchens.... So that interactions between my mother in law and me are fewer. We have separate kitchens now and this is within the 10 months of our marriage. Despite all this my mother in law and father in law keep finding things to accuse me of... His lost fixed deposit or anything that can't be found downstairs is understood as being done by me... They have even gone to the extent of saying that I have done some 'jadu tona'. Latest being that my father in law claims that "i" have written in his diary - 'ye Ghar aapko bechna padega'. This was the last straw for me.. I don't even speak unnecessarily with them and neither I go downstairs unless with my husband! Recently my mother in law has consulted a psychiatrist... She tries to emotionally black mail my husband, she finds every negative thing to say about me... With the current situation, I don't want to be blamed for anything that happens to my in laws or if there is falling out between my husband and his parents. As my husband has told his parents that if these things continue we will move out of the house. Please advise if there is some documentation that I can do, which explains the current state of affairs and that I am not responsible for what I am being blamed for... Should I file for defamation? I don't suit but a document to support my claims, if required.