Living wife for pensionary benefite

1. I am a veteran aged 65 years and have 75% disability. 2. My wife died last year on 28 Oct 2020. 3. I am staying with my mother aged 87 years and having been operated twice is bed ridden since 2014. 4. We had kept a daughter of an Army guy as an attendant since 2014. 5. She Is MCom and a muslim from Karnataka. 6. My wife had desired that she continues taking care of both my mother and I. 7. So as to preclude any stigma from society I have been advised to marry her. 8. I had approached courts in Haryana for obtaining a marriage certificate, they are ready to issue a “live in” certificate. 9. With a marriage certificate she will get status of “living wife” and thus be entitled to all financial benefits in recognition for her services rendered to mother and only surviving son. 10. How can I proceed legally to get a marriage certificate or is a “live in” certificate valid as a “marriage” certificate? Someone has drawn my notice to a judgement of Supreme Court as under:- 11. The Supreme Court said that if a man and woman live under the same roof and cohabit for considerable years, there will be a presumption of marriage under Section 114 of the Evidence Act. 12. Please advise me as to how to go legally forward so as that the Government recognizes her as a living wife to entitle her to all benefits that will accrue to her.