Wife Lying that I hided my first marriage

Hello All , I got married and divorced in 2012 which is not know to any one in my family or relative.I told this to my 2nd wife which is first marriage to her before marriage it self.She accepted and said as it is not know to anyone we also keep it secret as people may think in another way.After marriage she used to fight with me for everything and threaten me of revealing the facts If I dont do as per her wish.She use to chat and roam with lot of guys in her organization and If i ask her she will say I will reveal the fact to everyone and I will keep silent.Like this 2 years passed and 1 day she came with another person to home and I can't bear that and fought with her and I said tell to everyone np I cant bear any more the tourcher and informed to both families to come. Finally there parents came and started discussion went bigger and bigger and I came to know that they also aware of it from starting it self about my marriage and threatened me to file case If I dont do as per their daughter wish.I said no and they took her and went home and whie going he said you will come and beg me then I will talk to you its a warning. I dont want to go in a situation agaiin where I always say yes to there tourcher.1 year passed she and me are living separalty after 1 year she filled case IPC 494,495,420,498A D.P 3 & 4 on me and saying that she dont know about my marriage and I tourchered her everyday by beating .She didnt say that we are living separately from last 1 year. How to prove in court that she knows everything about my marriage and she left 1 year before from me .