He is slipping away or stepping back , because earlier he lived his life through them. Minding them, controlling them was pretty much his duty now he is trying to think of himself , just like they all are doing or were ding earlier. Cabir had Raghav, Mukti is dealing with Abhi, Dhruv did it with nandu and now with Alya . It's natural for them to raise eyebrows at him walking behind Nandu but thats the thing , it was the "wrong" of their group dynamics. Like Cabir said once, they will be happy if he lives for himself too. But for that they need communication. Something like post Musicana thing , to get their dynamics right.
I loved when alya was quick to retort that she knew all his friends, heck this girl was as obsessed with him for a long time too. He was her world, also as a friend she would be taken aback about any new friend. Very natural and subtle scene that one.
Word on the care part. It is even more essential during the intial bit where one is still trying to figure out the other , so many new emotions , behavior patterns to discover.