Why Is Marital Rape Not Criminalised In India?

Since January 18, #marriagestrike has been trending on Twitter after Delhi High Court's hearing plea on marital rape.
As part of the protest, some of the men are vowing to not get married if marital rape is criminalised.
In India, a man forcing his wife for sexual intercourse is not considered rape. Debates continue to arise around the laws on marital rape and its non-criminalisation.
Marital rape falls under the exception to rape laws which state sexual intercourse with one's wife who is over the age of 15 is not rape. It is a form of domestic abuse, but not recognised as a crime in India under the provisions of the Indian Penal Code (IPC), 1860.
Many continue to justify the exception of marital rape from India's rape laws as a way to protect the institution of marriage, avoiding further malicious prosecution against husbands.
The exception of marital rape from India's rape laws also throws light on the conservative Victorian values on which the Indian Penal Code was based.
India continues to remain one of the few countries alongside Iran, Afghanistan, South Sudan where the judiciary does not treat non-consensual sex within marriage as rape.