He is blinded in his own love for her. He cannot see past this truth in his mind... which is that Pakhi does not exist, and Sai is the only person in his heart. He is so engrossed in his own feelings, that he cannot look at things from Sai's perspective. If he actually understood how Sai was feeling, he would have ended the vaada and clarified things a very long time ago. Just the fact that he wants to confess his love and doesn't think to explain the past and clarify it to her shows that he isn't understanding Sai. Just like how Sai isn't able to label his actions as love. There is a huge communication gap here.
Not referring to the Vaada, I get that if they clear the vaada so soon they don't have anything more to spin stories and keep p in the triangle.
Was only referring to that particular scene. He knows Sai doesn't like him talking to P so why would she be ok to listen about their love story 🤔. In fact when someone is in love you tend to notice the reactions and mannerisms of the other person sooner than anyone else and understand something is wrong. And Virat does notice Sais minute change in expressions like we have seen in many scenes. But her they intentionally made Virat ignore Sais hurt so as to copy paste the next surprise party scene 🙄. Virat really looked silly not stopping the crazy yoga teacher sooner and thinking Sai is not hurt after all that she heard .