true, i agree with all of you but, at the same time.
Look. You cant blame Simi for believing Milli. All Simi knows, is there was a fire, Simi could've died, and Milli like she was back then, risked her life for the sake of her sister.
That is what Simi sees. She doesn't see, what the audience sees. Its not her fault. In fact, she is correct in her position. She is being a good sister in believing her younger sister no matter what over her husband. This makes sense. That is how its supposed to be in real life, you know? And Simi believes that Milli changed because Milli is insisting on it, and shows Simi that fake side of her.
Simi doesn't see her rolling her eyes, or trying to make Abhi paranoid.
One thing that doesn't make sense as many have mentioned, is why Simi isn't wondering how the fire got started in the first place.
Abhi sees her expression is fake, the tone of her voice when talking to Abhi is full of fakeness and mockery so he notices! Or, he too, if she was nice out of no where (in a more common-senseful' way as in, no ridiculous fire) would have thought she did change out of no where. If she stopped speaking to him that way, he too would be like wow, she got back to her senses. But no, the way Milli is acting towards Abhi notifies him that Milli is still screwed up. The way Milli acts towards Simi notifies her, that Milli changed.
Same with Vishal. Why would he believe Abhi, someone he isnt THAT close with, over Milli when Milli is "back to the same old her he fell in love with" in his eyes? Clearly, as audiences we know she isnt, but he doesnt and that isnt his fault. Its based on how shes being seen to each character. This drama, as annoying as it has gotten, although has many ridiculous problems with it, and lots of parts that dont make sense, is also very keen when it comes to making people stuck at a complicated position.
As for the prayer, I am pretty sure it wont work. It isnt valid, because Abhi is not her husband, right?
Once it works, for some stupid reason, we can then all complain.
But Abhi wont fall in love with Milli ever, that is one thing we can all be assured about :)