I finally get this sudden change in Satrupa and realized that it isn't as sudden as it appears so I'm sharing my thoughts here.
Let's start from the beginning. Satrupa was chosen for Baldev and married to him in an arranged marriage. Probably because both were of high status this arranged marriage was decided by parents and the two had no choice. They get married and at some point Satrupa finds out about Sudha and Baldev. We aren't exactly told when, but she does and she realizes that Baldev doesn't love her and the pregnancies are just because the family needs a heir. Anyone in her position would become highly disturbed at this point. She is a baby-making machine. That's it.
So what does she do? She decides to make the best of the situation and takes over the business and does what she can for her kids. She starts playing politics in her own family. She is basically doing what she's been shown. Gayatri and Vikram played politics with her to get a legitimate heir. Baldev played politics with her by getting married to her despite loving another. Even her own parents played politics with her by getting her married into a rich family, not caring about her feelings.
Then she goes on to lose her first two children before they are even born. At this point she's been battered from every angle, emotionally, mentally, and maybe even physically. She gets pregnant a second time and she will do anything to ensure nothing happens to her children, even if it means imprisoning them in their own home.
Guruji told her that her child's life is in danger and she needs to give him away to keep him alive. But now she's had enough. The family needs a heir and Vikram will only accept a grandson as heir. She plays politics with her own kids and gives away the daughter despite Guruji's testament. She thinks she can protect the child that she keeps with her possessive and obsessive behaviour.
But we human beings are of a unique nature. When pushed again and again we retaliate. We start doing the opposite of what is being told to us. Our parents push us into engineering, but we decide that we'll do arts instead. Our parents tell us to take that multi-national job, we decide to go to that start-up or open our new business. Our family tells us don't go out because of the riots, we choose to go out that very day and get stuck in the riots. Push and we push back.
That's exactly what Vatsalya did. Satrupa pushed and pushed and pushed. She put up barriers. She put up protections. She put up a bodyguard. She did everything and yet the one thing she couldn't control was Vatsalya himself. Vatsalya ran away. He escaped and that escape led to his death.
Up to this point Satrupa had been doing what had been done to her. She had nobody of her own except Vatsalya and she would do anything to protect him. But with him gone she got pushed into an abyss from where there's no return. She was left all alone in this heartless world. So she tried to kill herself to join the person she loved the most and who loved her the most, but Guruji arrived at the right time and saved her. Reminded her that she still had another child. The child that was supposed to have been the rightful heir and yet was pushed away just because she was a girl.
Satrupa now had a new reason to live. Anami. She brought Anami back to LM, but incorrectly. She forced Anami back just because she believed she had a bloodright on Anami. That was her first mistake. I would even call it the fatal mistake because that mistake has led to many more.
Now here's my thinking as to why Satrupa did what she did. When Satrupa got married to Baldev, she probably wasn't as cunning and political as she is today. She was shrewd and smart no doubt about it, but the betrayals taught her politics. For 20 years or so she was part of LM and she was allowed to play her politics. Vikram supported her because she gave Royal Steels a new life and took it forward. Gayatri hated her for this, but didn't stop her. And the rest of the family didn't much care or fight back. So she was given a green light to do whatever she wanted. This became a part of her behaviour, her thinking, her morals. When she found out about Anami, she did what she had been doing forever. Played politics. Blackmailed her own daughter. And that was her fatal mistake. Anami hates her and if you push someone who hates you to such an extent, then that person will just hate you more.
Still Satrupa managed to bring Anami back and in Anami she saw Vatsalya, but more than Vatsalya she saw an opportunity to prove that she could never be wrong, that she always knew what was right for LM and RS and will always know that. But Anami proved untameable. Yes Satrupa learnt from some of her mistakes. Instead of a bodyguard she gave Anami a companion, a shadow, a sister. Instead of stopping Anami from doing stuff, she used reverse psychology and politics to get Anami to do exactly what she wanted Anami to do. Instead of telling Anami off for her mistakes, she convinced the family that Anami would correct her own mistakes like bringing Sudha into LM.
But then Anami did exactly what Vatsalya had done. She pushed back and ran away. Satrupa lost the only person she loved dearly yet again.
Now push anyone too much to the brink and at some point they'll go over it. Anami running away was that push over the limit. And it shows in Satrupa's behaviour. She lost her mental stability. She was willing to do anything and everything to bring Anami back. But in the process she ended up looking even worse in Anami's eyes.
Anami is back, but is no longer anything that Satrupa recognizes. Yet Satrupa does not understand. She blames others. She is obsessing over the old Anami. She is possessive about this new one. And she will do anything to keep Anami close because in her eyes blood relations are more important than heart relations. And she's not to be blamed completely for that. When she entered LM that's what she saw. So of course she'll follow that.
Since Anami ran away to today everything Satrupa has done has been in that same possessive nature to bring Anami back. But now it's no longer just about keeping Anami in LM. It's about getting rid of anyone who could pull Anami away. She might not have wanted to kill Anami's adoptive parents, but it appears as such. And now she's trying to push Adhiraj away as well.
Note: I'm not justifying anything Satrupa is doing. She's wrong. Very wrong. She needs to realize that she's making a big mistake by blaming others and not herself. Only then will she really get close to Anami. But today I understood her and that's what I've tried writing down here.