Having Lots of issues with my Marriage

Dear Advocates, I dont want to become martyr of marriage. I got married in 2010 and the problem started withing 6 months of marriage. I have been giving her chances again & again since that time & expecting things will change & it will be better but invain. I have been thinking of writing to you since a very long time but i somehow stopped myself from doing so. My Wife is very short tempered & for her the family is only me,herself and my 3 and a half years old son. She hates my parents & hates my mom the most. She has threatened to end her life many a times when the argument happens.I informed her umpteen number of times why do you say this its not right...but thats her practice i believe.She can argue on any damn thing & make an issue out of it and then once that is over she will link old stories to drag the argument. I have tried my best to be very understanding with her & tolerated all her wrong doings infact hidden her wrong doings as well. Infact i wanted to inform her dad about her but my mom asked me not to do it since she is young things will change with time as even she is new but it has gone from bad to worst. She also threatens to kill my mom when she is angry, she uses cuss words against her... she uses abusive language as well im tolerating all this things because i read some things about 498A and my life will be destroyed if she files a case. infact she has threatened that if she does anything to her life she will write a letter and name my MOM in it. During an argument once my mom consumed excess of paracetamol because my wife during the argument again threatened to end her life instead of that my mom told her "since you tell this all the time , let me end my life" My mom confessed that she has done something wrong but she is not going to tell my wife ( on the phone as i was at work), later she told she consumed paracetamol. I went to the Police station & told them that MOM consumed it by mistake ( now even this time i shielded her) But now she is crossing the limit & its becoming very unbearable. What shall i do, i may want to get separate from her because i gave her too much time to her to become a little sane but i dont see any difference. Also, during the marriage we took amount of 2.5 Lakhs from her family instead of TV,Fridge,Motorcycle etc... ( This is dowry? but there has been no harrassment from my end or my parents end infact she is the one who is harassing my mom and me). My Dad is unaware of all the arguments which is happening at my house. My Wife tries to posion my mind by saying your parents are using you & havent looked after you very well when you were a child its your grandfather who took care of you. Kindly help on my fears pls. your's sincerely, Rahul