Marriage annulment

Hi learned folks, I would request your opinion on the following situtation: I am 36 years old married since the last 2 years. My wife has not stayed with me for approximately a year. At the time of courtship, she denied having any past relationship and it was only after this discussion, we married each other. A couple of month ago, I came to know of her past which she herself informed me about. Now I feel betrayed and feels like being used by her and her family. Her family on confrontation, says that almost all girls have a past these days so move on from this. The girl is now back to my rented apartment and is not moving to her parents house. She was also suffering from PCOS/PCOD in both the ovaries even before marriage and we are unable to conceive a child. Can my marriage be annulled on this fraud? I have discovered this a couple of months ago and she is now back from her fathers place to my rented accommodation. What - Please advice shall I go for marriage annulment or a divorce? When - when shall I file this case. Shall I give her a chance for a 4-6 months window or shall I file a case immediately?