I am so sad because knowing all this he dragged sona into this mess.
But , if am correct- that is why he didn't try anything post break up.
He didn't try to convince sona.
Because it was obvious that he can't go against his mother.
Now sona has chosen this life.
She can't complain to Dev now.
That is why sona is hell bent in pleasing iswari.
Because she knows he won't take a stand.