My wife mentally harassed me

Hi, I'm married for 6 months and my wife has already started threatening to give divorce and file dowry case against me and my parents. She keeps on saying that "I will ruin your life and your family's too" My wife mentally harasses me every another day and demands a new demand each day. She also threatens me that She'll commit suicide, leave my house, split up & live alone and ruin my life permanently. She picks up fights on small matters. She warned me many times to be prepared for adverse consequences. How can I safeguard myself and my family. Can I give a letter in police station to protect us from any unpredictable circumstances arising from her or her family. We have not demanded or taken dowry, but she regularly keeps on saying that your mother is very demanding. She didn't brought much clothes with her and family gave her sufficient clothes, but she is never satisfied from anything I or my family does. What can we do to protect ourselves from false cases? My wife also claims that my sisters are interfering in our married life. Can she name my sisters in false complaints? My family and I are very worried from the consequences that could arise. Please advise me ASAP. Regards,, Nitin Choudhary Jaipur