The most abusive one is between Akheraj and Harki. Harki accepts it without a complaint, without a frown. Stockholm syndrome?
Between Basant and Gehna. Gehna even left home but returned and made peace. A small village girl from an impoverished family who sold her to dadisa.
Between Sanchi and Saurabh which is much more contemporary. Sanchi willingly went with Saurabh against all good advice and then she realised what Saurabh really was. then it was too late and she had to face consequences even when she married his elder brother. Sanchi is from a big city and from a well to do family who did not know what was happening with her. They were quite conservative with such things though.
And there was one more short lived abusive relationship between Kundan and Urmi which ended up with Urmi's untimely death.