I knew Zoya would change in some way but I never thought how. Your points lit a light bulb in my head.
She is soo going to become subdued, serious, mature and lose her independence. It reminds me of Kareena's character in Jab We Met. The immature childish carefree Geet who followed her heart became someone serious and mellow until Aditya brought her back to her real self. Asad would do that for Zoya. During this time I imagine Zoya going through a lot of emotional n mental turmoil due to finding out her past/father and/or [possibily] getting and being married to Ayaan and going through hell in his household. Asad will be what Aditya was to Geet, her support and lifeline.