Wonderful analysis ! And some of the other comments too are amazing! There is nothing much I can add.
My two penny bit:
Your character analysis is exactly the perspective I keep about Sai.
During the Holi episode, when she explains to Pakhi about the thandai. She says something very pertinent. She says I get my high from love and from life itself. She has maintained this. Even during the Nag Nadi date, she said she revels in the moment, as it is going on and she enjoys very small things that give pleasure. This is also a survival tactic - a positive tactic I must add that people who have been through trauma in life adapt, to keep themselves from brooding.
This does come from her father. there must have been so many instances when she felt the need for a mother or felt bad when she saw other children with a complete family. KJ has taught her to always look on the bright side of life. And at a very young age she learned to count her good moments in life.
When Sai loves someone, she can give her life for them. When Jagtap threatened her he would killl her dad, she was willing to get married, she gave up the fight, even when Virat was there. She just thought of handling it her own way even if it meant marrying such a horrible person.
I don't want to think about her love for Virat because her realisation is at a stage when she is extremely vulnerable. Virat is also a product of his upbringing. Literally, look how he separated the bed just like his parents! . We are all a product of our upbringing and keep going back to our childhood, revisiting situations and behaving just like our parents would!
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