AsMi (Ashok and Mihika) are not going to break up. Raman will find the truth and might take Mihika back but don't think AsMi divorce will happen.
Shagun will have to remain single for a long time. That is the worst part. She will keep troubling Ishita and Raman from time to time, even if she lives far away fro them.
What will happen to Adi? He is changing but he still loves his mom unconditionally. If Shagun has to leave Iyer house, he will definitely go with her.
If Mihika comes back with no strings attached (divorced), she will have to be paired up with someone else. Mihir won't come back as he's married to Rinky. There is a possibility that Mihika-Romi might happen.
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