Couple lives in uk and marriage solemnized in india

your marriage was legally recognised in the country your marriage took place, you can commence a divorce in England if you are habitually resident or domiciled in England or Wales.

If your friend has not withdrwan the Indian citizenship and retains citizenship of India then she can file Divorce petition as provided by the Act under section 19(i)

19. Court to which petition shall be presented.—Every petition under this Act shall be presented to the District Court within the local limits of whose ordinary original civil jurisdiction:—

(i) the marriage was solemnized, or

That means she file in India, but she should mention that she is holding dual citizenship of UK and India

Respect exerts, 

Thank you very much for your help 

British passport holder with oci. British citizenship  yes. She has single citizenship of uk at present . Thank you once again 

The citizenship of your friend will not restrict her from filing divorce case in India on the grounds of cruelty for the marriage that was solemnised in India as per Indian laws.

She can travel to India, file the divorce case, conduct it properly and get her marriage dissolved by a decree of divorce on merits.

Ask her to contact any experienced lawyer in India and proceed as suggested.

Thank you very for the reply sir 

You are welcome for your appreciations