Without taking divorce My husband is trying to null our marriage certificate and wants to remarry

Hello sir, I married before 4 years ago.In starting days my father and mother in laws are good behave with me but after 15days they started quarrel with me as they need dowry.my husband was also with their parents he also torture me daily .within 2 months i came to know that my husband has extra martial affair.i have commited sucide because of my mother in law mentally torture and my husband's extra martial affairs. My parents came and took me to my home. My husband apologised and wants to live with me but his parents does not want to me in their house and they push my husband to take divorce. Before 1.5year my husband has given one side divorce notice without any signature in divorce documents. In that answer i have also given notice that our marriage is not over still continue. We have done register marriage also and my husband know this truth.Before 8 months my husband has done FIR against me that my wife has received marriage certificate alone without my signature. And now he wants to void that marriage certificate also and remarry.i do not want to give him divorce as i want to live with him. Can my husband marry any girl without any divorce? Without any signature in any documents?Can he keep any girl in his home and mention that i will live in relationship? Please help