If the husband has made efforts to bring back the wife during the 2 years period of separation and the wife has refused to co-habit .... then u can claim it is desertion ...... U claim your wife suffers from mental disorder problems .... if this is true you can file application for nullity of marriage in the famlly court .... But it wll be necessary to prove her mental disorder condition
11. Nullity of marriage and divorce- Void marriages.- Any marriage solemnized after the commencement of this Act shall be null and void and may, on a petition presented by either party thereto, against the other party be so declared by a decree of nullity if it contravenes any one of the conditions specified in clauses (i), (iv) and (v), Section 5.
5. Condition for a Hindu Marriage.- A marriage may be solemnized between any two Hindus, if the following conditions are fulfilled, namely:
(i) neither party has a spouse living at the time of the marriage;
(ii) at the time of the marriage, neither party,-
(a) is incapable of giving a valid consent of it in consequence of unsoundness of mind; or
(b) though capable of giving a valid consent has been suffering from mental disorder of such a kind or to such an extent as to be unfit for marriage and the procreation of children; or
(c) has been subject to recurrent attacks of insanity or epilepsy;