Is a live in relation legal if i am a married person?

To live in a live-in relatioship is legal, provided that you are not at the same time married to another woman. If you are married, though seperated / or not living with your spouse, and living with some other lady, you are living in adultery, which is a ground for divorce.

Now coming to your situation that your wife is not living with you, you can file a petition for divorce on various grounds as provided under the Hindu Marriage Act, provided you are able to prove those in the court of law.

However, you can also talk to your wife and if both of you are agreeable, then you can opt for divorce through mutual consent, but you have to wait for one year of seperation for the same.