Property in dispute

If the sale deed is registered in both the names of the husband and wife, the wife has a half-share in the property and the absolute owner for her 1/2 right.  If the sale deed is registered in the husband's name, the wife cannot claim it.

As informed by you that the property was purchased on both the names, then both are equally entitled to their rights in the property.

The payment of EMI by one person alone cannot deprive the rights of the other person.

You can amicably settle the issue or can file a suit for partition to allow the court to decide

As property is named on both husband and wife so both are joint owner of property, one of them can't claim his/her ownership exclusively on basis of EMIs deposited by him/her.

Being co-titleholder (co-owner) of the property she may gift or sale her share to you in lieu of payment of balance of consideration through EMIs. 

Convience, persuade or prevail upon her views through near and dear ones, elderly respectable persons of society, relatives etc., if you cannot take on directly.