Aryaan was wrong to blame Suvarna for him becoming a criminal. I agree that Suvarna was wrong in what she did by giving Aryaan to her brother, but Aryaan choose the wrong path to get back on Suvarna and Manish as he thinks even Manish knows the truth as he listened to a conversation of theirs and misinterpreted it, because the reason of her leaving him was Karthik so he decided to target Karthik but he also knew that Suvarna was hiding this, hiding that she and Manish had a son which was him, Aryaan, so that means no one else knew. He stayed with the family for a while he must have known what Karthik is too everyone, too Naira and Dadi especially. He wanted to punish Suvarna and Manish but anything going wrong with Karthik would hurt Naira, Dadi, Akhilesh, Surekha, even Singhanias, didn't he think about that. It was his choice to hurt Suvarna Manish at any cost using Karthik not realizing that many other innocent hearts who had nothing to do with the wrong that happened with him would also get hurt. It was his choice. Hurting people who did no wrong to him, choosing the wrong path to get back, it was his choice.