Mental & emotional torcher from mother in law

Hi , its been 15 years that im known to my husband , who has a frd for 5 yrs and later we are married since 10 yrs . This relations was never welcomed by my husband's mother. She has tried to stop this marriage earlier with black magic stuffs, later had to give it up and agreed. But the silent torches could not stop ,though she might have thought , she can create issues and separate us.that isn't working all these years but the silent torches is increasing every day. Creating doubts abt me to my husband , showing people a different image.If asked, on any point abt her deeds, she goes to a sympathy /empathy face...giving reason of her health conditions & other mental issues ... has become the common reasons since 15 yrs. As we belong to a Hindu customed family. My father in law ,shows support though he knows the issue , making me wrong always though he is a good man. My husband is most of the time silent and watches the shows however behind he knows the house situation. Im the only fighter for myself and not getting any support actively. i want advice so that i can go legally and stop these coming to me once for all. Pls advice.