There were a few undercurrent statements in Yash's behavior yesterday. In the beginning, he was in denial. Not only in denial of his feelings for Arti, but more importantly his denial for their relationship. He DID MARRY her, but at the same time, he was in an illusion, and evading himself of his responsibilities (emotionally and morally, not physically) as Arti's husband.
After the blow up at the party, specially after every one bashing him, and he raelizing that Arti left him just out of fear that he will not accept their unborn kid was a jolt for him. He realized how unfair he has been to her. Arti is not a toy. Their relationship is not a game. They are married and that he needed to be, if not anything else, fair to her.
His behavior to her is a combination of his guilt (for mistreating her), his respect for her (that despite how she feels, she has stood by the boundaries he had set) and more importantly a new found acknowledgement of his relationship with her.
He had already accepted Ansh as a son, which explains his emotional reunion with him. But with Arti - he had almost negated their relationship in his mind, so today was the first time he was acknowledging it. He was releived that he now had a chance to undo the damage to some extent. His words "apni biwi aur bache", "mera parivar mujhe lautana", "aap mere bacho ko", "ghar pe sab aapka intezaar" etc., are a statement of testimony that he finally accepts Arti as his wife/family.
He still, however has not realized that he loves her. He just wants to care for her, and undo the damage he has done to her (still unbeknown of the fact that she has endured a lot past few days - including the complicated pregnancy, the hospitalization and a lot even before that, in terms of abuse from Prashant).
What he is doing is more so out of an acknowledgement for their relationship as man and wife. Specially when he says, "ab is ankh micholi ka khel mein aur nahi khel sakta" is like him almost acknowledging that he does not want to play this game anymore, and that he now wants to take a stand and stick to it - which is that Arti too, is his family.
Does this mean, he realizes, he has fallen in love with her? in my opinion, no. That journey is yet to start.
Add to that Arti's new found awkwardness now... She loves Yash. She is happy he has accepted her baby. But she is not used to him taking care of her. She is infact not used to anyone taking care of her. And, she doesn't know if she can trust this "new Yash" long term... In the sense, she knew he warmed up to her in Mumbai, but then the moment they got close... he retaliated. So to her, does that mean, just because he accepts his responsibility towards his baby , he loves her or has given her the right to be a rightful wife in his life - no! So, though she is happy with this change... she is still a bit vary of what to do with this new turn of events in her life.
That arti is falling in love with him all over again , and that even at this stage we are getting butterflies in our stomach, watching him go all caring and gaga over Arti, ... hmmm, God only save us from what we see in the future. š. Hope to see that beautiful journey from a deep respect and care to love...