Seeking sepration from wife

Hi, I got married on 8th Feb 2014, I work with an MNC Bank drawing around 50k, while my wife works at a leading newspaper as an assistant editor. I belong to a homely family & the main bread earner of my family. In the starting of marriage my wife demanded to take her out few times, which we did. I used to do nights shifts due to which mybiological clock is set in a way i sleep around 1-2 am in night. Where in my wife works in a proper morning shifts. I spend my time @ nights, following Twitter & chatting with my friends. I am still friends with the ex's one of whom is happily married & got a kid in pune, & other one is still unmarried & working in my organisation. She got few proofs of my past relationship with the same girl. My wife keeps on torturing me with questions related to my present relationship with my colleague. She is even harassing me that she has evidences of me and my colleague being online together on whatsapp for conversation. She is blaming me of emotional infidelity. However, i have seen her chats with one of her relatives, abusing my parents & badmouting about them, & when i confronted her with same, she sd it was my other relatives who used to fill her ears with bad things abt us. Though they deny to do so & have told me about all the things, abuses & accusations which she said about me, my parents. This to fact where my parents have been real supportive of her & question me on my current status with my ex on her behalf. Of late the atmosphere @ home has been real bad & so is relationship between us. There have been constant fights between us, on every petty topic. I have undergone through a dreadful phase of depression, and still suffering from sleep disorders. She has failed to give emotional security to me. She intends me to leave my family & stay on with her seperately which i donot want to. She has been asking me to take a final decision about our relationship, if we would want to continue or not. I donot want to continue with relationship & am just not able to take that decision as i feel i would have to pay her a lumpsum amount, which i donot have & about the 498A & other legal courses which she would take against me & my family, which i donot want to see.