On Holi, Virat picked Sai over Pakhi and this hurt Pakhi. But the root of all the problems is not addressed. Who the hell spiked Sai's drink? Imagine if Sai had been drunk that day? Pakhi wanted to humiliate another woman. But Pakhi will not reflect on her evil intentions. If she had not spiked,there wouldn't have been any such scene.
From the beginning, she has been the cause of her own problems. She married Samrat despite Virat clearly telling her that he can't marry her even if she doesn't marry Samrat. She wanted to stay close to Virat so married Samrat. This woman was comfortable with the promise that Virat will not let anyone come into his life. Matlab, see the selfishness. You live with his brother and let him stay single.
Because of her disrespecting her own marriage bed by calling her ex and romancing with her ex over the phone, her husband left her.
Later, when her husband returned, she never tried to nurture her own marriage.
Then after Samrat died, she did the surrogacy kant instead of moving on in life.
Virat clearly told her that i can't love you and i am only marrying you for Vinu. But she married him. Why wouldn't the woman who is comfortable with becoming the bhabhi of her ex because she wants to stay close with him, marry this ex and be called his wife? There was no bloody sacrifice.
She is her own problem. She is the cause of all her miseries. See, karma exists.