what is contribution made by you for purchase  of house?

2) you can file declaratory suit that you have x per cent share in house as funds contributed by you 

2) to direct wife to deposit your share of rentals in court 

make an application calling upon wife to deposit rentals in court as you are co owner of flat 

If your wife is paying the EMIs with rental income, then you should approach the court and request an injunction to prevent your wife from using the rental income to pay the EMIs until the divorce proceedings are finalized. This will give you some leverage in the negotiations.

If the house property is on the joint names, then you can initiate legal action by sending a legal notice to her for partitioning the property.

Even though the property cannot be partitioned at this stage when the home loan has not been fully discharged, let she give a reply after which you can approach court for relief and remedy. 

If the property is fully on her name by a registered sale deed and you are just a co-applicant for the purpose of loan and you have not been paying the loan EMI, you may not be able to establish your claim for an equal share in the property, hence you may revert with more details for a proper legal opinion. 

If you have the evidence to prove the amount what you have invested in this property, you can either demand the same with interest from her by informing her that you are ready and willing to relinquish your rights in the property or to divide the property and allocate your share in the property.

You can file a suit for partition and can demand your share out of the rental income or to obtain an order of injunction restraining her either from collecting the rental income or to not to let out the property on rent till the disposal of the court case. 

- If you are joint owner of the property , then she cannot take your share in the property and also rent from the said house. 

- Since, you have paid 15 lakhs to the bank, then you can ask for the refund of the said  paid amount after sending a legal notice to her , if she is in possession of the property through the tenant. 

- Further , if she is not responding , then you can file a declaration suit before the court for declaring the owner of the said house after submitting the proof of payment and on the ground of rent from the said house. 

You can execute POA in favour  of family member to file case on your behalf ,to appear in court on your behalf 

- You can execute POA in favour of any relative or nearest one living in India for engaging a lawyer and to contest the case on your behalf. 

- The said POA should be notarized as per rule of US , and attested from the consulate of India. 

If you are really serious about your money then you must take proper legal action as per law.

As a matter of fact the evidences in your possession may not be sufficient to recover the money you invested because they appear to be barred by limitation.

In any case if you don't follow up the case by visiting the court whenever possible, you may not be able to conduct the case properly from a remote place even though you may appoint a power agent to represent you during your absence before court.

You can decide accordingly.

You can contest the case agressively on merits to compel her to settle the matter. You should have some good evidence which is against her to pressurise her for settlement 

Dear client,  

As a co-borrower of the joint housing loan, you have a legal right to access the loan account and have a say in the decision-making process related to the loan. You can take legal action against your wife for denying you access to the loan account and rental income. You can also file a petition in court seeking a direction to your wife to provide you access to the loan account and rental income.

Further, you can also approach the bank and inform them of the dispute between you and your wife and request them to freeze the loan account until the dispute is resolved. However, the bank may not be willing to do so if your wife is paying the EMIs regularly from the rental income.

If the divorce case is still pending, you can also file an application before the court seeking interim relief in the form of a direction to your wife to provide you access to the loan account and rental income until the case is finally decided.

In any case, it is advisable to consult with a lawyer who specializes in family law and has experience in dealing with similar situations. They can guide you on the legal options available to you and help you take appropriate action.