Not sure if I can put my finger on it, but there was something missing when Neil and Ragini confessed their MUs to each other and how each was so wrong in not believing the other.
It wasn't blissful, it was incomplete. Ragini cried and cried. And Neil agreed he should have tried harder to convince her 15 years ago. He didn't mention the phone call at all.
Instead of groveling in front of Neil and making it look like it was ALL her fault, Ragini should have pulled herself together and asked Neil why didn't he try harder 15 years ago? Why did he not make an all out-effort to convince her that Suhani was not his biological child. Why didn't he chase down Ronnie, get a blood test, get a DNA test, get his friends to counsel Ragini, stalk his wife until she became convinced. WHY did he let it go? Quite frankly, Neil's behavior at that time was almost like Suhani WAS his child and Ragini can like it or lump it!
The Neil we saw in the Flash Backs was a little emotionally detached. It is difficult to gauge how he felt about keeping the Roopali-secret from his wife. Was it just a matter of fact for him? He was not doing anything wrong, then why on earth would his wife have a problem? And why does his wife need proof about the baby? Is his word not good enough? At a different time and place, in different circumstances, it may have been enough, but not where they were in their marriage, only 4 years into it and four little children, and a wife who was insecure at the best of times! (given Neil's past) They were starting out and navigating a complex new relationship.
It is easier to relate to how Ragini was feeling at that time. A young mom with four small children, no sleep, her body changing with child birth, feeling unattractive, a husband who was busy pursuing a very high profile career. And then in midst of all this, an old girlfriend pops up. And much to Ragini's horror, the ex is pregnant. And when confronted by the wife, the ex-lover gives her very ambiguous answers! Ragini's paranoia takes over. But Neil couldn't see any of this. He wasn't thinking like a husband.
But why did he so easily agree to the divorce? It was almost like, "A divorce? Oh well, whatever. Divide the kids? Sounds like the plan! I am off to New York. Don't call me."
Their reunion looks a little hollow to me. So much bitterness is still hanging in the space between them! So many questions still need to be answered. And all along, Neil really did have all the answers. If he loved his ex-wife so much and was "possessive" about her, as he claimed, why didn't he try again? Why leave it so long? The big question is, would anything have changed if his daughter Nishi did not make the first move?