Wife is mentally ill before marriage but not disclosed

I got married 12 years ago at bahadurgarh(Haryana), living at dwarka(new delhi) sice marriage,i am prfessionally qualified and post graduate but my income is not much,age 45 years,wife's age 43 yrs , my wife is mentally ill but my inlaws not mentioned any thing about this but after few days we came to know that my wife was already under treatment before marriage and taking medicines like oliza 0.5 ,risdone,pacitane etc,when we asked them they told us that due to death of her mother before six months of marriage she got depressed and requested us to continue the medcine and she will be cured or remain stable,due to the old age of my parents i decided to continue with my wife ,last year my beloved father expired,my mother can not live with me because of my wife's rude and mad behaviour i tried my best to continue with my wife but she got more and more lazy, senseless,and she has no sentiments towards any one or any things she doesnot take bath for one month and even for two months,she does not change the bedsheet even for six months ,dont brush teeths etc.dont take interest in any thing she runs away from my house to my inlaw's place for which i have complained to police in written , at present she is at my inlaw's place for about three months after one year of my marriage i was blessed with two sons, both are 10 yrs old now but now things are out of control as she always talk about suicide, dont do any household work,some times cries or continuously laughs , wake-up at midnight and switch on the lights my inlaws are making pressure on me to take her back and threatning me with dire consequences, my apprehensions are 1. what will happen if she commits suicide at my place or at my inlaws place 2.what will happen if she kills me or my children 3. if she runs out of my house or met with any kind of accident or kidnapped etc 4. if i apply for divorce at which place the the court proceeding will happen i.e at bahadurgarh( place of marriage) or at dwarka(where i am living ), if my inlaws start court proceeding at bahadurgarh ,is it is possible for me to change it to dwarka, i have only hospital slips of different govt hospitals and one reputed private hospital but not concrete evidence to declare her mad