I guess that's the biggest complaint people have, they wanted more depth to Sejal and a backstory to Harry's character and I completely get their point. However, sometimes it's ok to show things at a surface without necessarily having to explicitly say what the character's issue is.
I always use this example but remember RDB? There was a scene where Siddharth's character opens his drawers and there's a picture of a woman there. It's never explained who she was, most likely his mother...maybe someone he loved?? It's up to us to interpret. We also get hints that he actually liked Soha's character himself. Again, never openly shown but many people took that interpretation.
With Harry, you had the flashes, the reminiscing of 'home' especially when he's with Sejal so he's lonely. We get that. With Sejal, she starts crying after she's molested in the club and she breaks down saying 'Rupen would blame me, he thinks I can't do anything right' - so she was constantly reminded of her flaws. She was constantly looking for that approval which MANY GIRLS in today's time unfortunately need especially from a lover.
As far as RDB is concerned, I remember having read about how Siddharth's character was in love with that of Soha'. I couldn't pick it up after the first watch. But it did make a li'l sense when I watched the movie again.
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