1. Marriage has, for the longest time, been economically driven. Mixing romantic love with marriage is a recent construct, largely driven by media and hollywood. Take a look at writing by Stephanie Coontz.

2. India is very different from the modern west. Compared to the US, India has ineffective government, corrupt policing, and lack of rule of law. One cannot realistically expect courts to resolve conflict fairly in reasonable time. In such societies, community bonds, tribal loyalties, and by extension, alliances formed via marriage tend to be very important for survival. While India is slowly developing economically, the average middle class (including your parents) still seems to be stuck in the past. Give them some time. As they feel more secure and feel less need for community and tribal alliances, their attitudes will change too.

3. If you really want to dig deeper into truth, consider that marriage and monogamy is a cultural concept, not a biological one. Monogamy is a highly misogynistic construct that is rooted in male desire to ensure “paternity certainty”. Humans have lived on the planet for at least 250k years. Monogamy appeared once settled agriculture started, merely 30k years ago. There have been many cultures before our time that were very matriarchal, and monogamy was not imposed nor expected. Take a look at Christopher Ryan’s works.