Lot of us are debating the fact that Sonakshi forgave him without him asking for forgiveness. That she has no self respect. No redemption track for Dev etc etc. But it's not that she hasn't been upset with him... In fact sometimes even harsh and cruel with her words. But all that anger went away when she saw him in pain and saw his suffering.
Remember he is perfect to her with all his flaws because it's her heart that chose to love him. Her affection will always come before his perfection. So there is no question of an apology or self respect. I am sure that'll be taken care of as the story progresses.
The main reason why she forgot and forgave was to let him know that what he did to her was painful but what he is continuing to do to her was not only painful but something that she would not be able to endure and survive. She is worried about her own pain but also the misery that he is going through. As seeing him in this state only intensifies her suffering.
So all in all a beautiful episode for me. Made even more brilliant by two fabulous actors.