It is not illegal to be in a live-in relationship with a woman of your choice provided he too has the same desire to live with you, irrespective of the fact that she is a married or unmarried woman.
In another landmark case filed by actor S Khushboo, the Supreme Court had said live-in relationships are permissible and the act of two adults living together cannot be considered illegal or unlawful
While it is true that the mainstream view in our society is that s*xual contact should take place only between marital partners, there is no statutory offence that takes place when adults willingly engage in s*xual relations outside the marital setting, with the exception of `adultery’ as defined under Section 497 IPC, it said.
Notions of social morality are inherently subjective and the criminal law cannot be used as a means to unduly interfere with the domain of personal autonomy. Morality and criminality are not co-extensive, the court said.
In 2013, the top court in Indra Sarma vs V K V Sarma said, Live-in or marriage-like relationship is neither a crime nor a sin though socially unacceptable in this country.
A long-standing relationship as a concubine, though not a relationship in the nature of a marriage, of course, may at times, deserve protection because that woman might not be financially independent, it added.
In view of the above contents, in my opinion there is nothing wrong in you choosing a partner of your choice be it a married or unmarried woman as long as you do not compel her or coerce her into this kind of relationship.
Live-in relationships, though not socially accepted in India, do not amount to any offence under law, the Allahabad High Court recently ruled reaffirming that two consenting adults are at liberty to live together and no person would be permitted to interfere in their peaceful living
You may make sure that you do not marry her without she getting divorced from her previous marriage
