I think marriage is a necessary institution for us as humans. It's not just a social contract, but a path towards spiritual growth. It's a way to progress on the path of self-realization and ultimately achieve liberation (Moksha, *something that I learnt being a Hindu by birth).

In Hinduism, a man is considered incomplete without a wife, and a wife complements him in his journey towards Dharma, Artha (wealth), Kama (desire), and Moksha (the liberation from the bondage of life and death).