Imagine if Aman and Anjali got married. It wouldn't be a disastrous marriage by any means. Aman was a GREAT guy, perfect in all ways and loved Anjali immensly but what about her ?? She only found out the meaning of true love when she realised she had fallen for her best friend Rahul. Its not that Aman wouldn't keep her happy but he just wasn't Rahul! No matter how much Aman loved her, she wouldn't be able to reciprocate those feelings because she would have to live with the fact that her first love was left incomplete.
Similarly, Riddhima will only ever love the guy who made her realise what love is. I've heard people saying 'eternal love' doesn't exist etc. But films and serials aren't made to face us with reality! Isn't the real world harsh enough anyway? We become addicted to this form of escapism because its how we wish our life was. They are there to make us believe that good things happen to good people.
Riddhima can't move on while her first (and last) love is still alive, still madly in love with her. She can't be happy with anyone else but Armaan 😊