Actually, before 2018 infidelity or adultery was a punishable offence. And you might have been able to file a complaint against the sexual partner of your wife. But in September 2018, the apex court has declared Section 497 of the Indian Penal Code (IPC) – that makes adultery a punishable offence for men – unconstitutional and struck it down. Now adultery or infidelity is not a punishable offence anymore.