Ani never did anything wrong knowingly. He was slowly falling out of love (if it was love) with Arshi and falling in love with J. Hence, during this phase, he was emotionally attached with both to some extent.
However, even with his increasing love for J, he never ever thought of calling off his marriage. It was always Arshi who talkd about breaking the relationship. Ani never thought of letting Arshi go and at the same time prevented J from leaving him. If you fall out of love with someone, the right thing is to call off the relationship. Ani should hv called off the relationship independent of if J loves him or not. Arshi remained Ani's back up plan, unknowingly, which is wrong.
The big difference between Ani and J is that J has high morales whereas Ani is a spontaneous person. Ani does not much think about right and wrong. Ani needs to develop a better sense of morales and for J, the importance of morales should decrease to level of practicality. If Ani has fallen out of love with Arshi, compulsing him to marry Arshi, for sake of committment would be wrong.
J since marriage, remained committed emotionally to Ani, whereas Ani's committment wavered with situation. J agreed to marry for sake of Ani, whereas Ani, celebrated rituals with Arshi to hurt J.
The situation for Ani and J is not that simple. They have to overcome the challenges of morality, their believes about each other, their class differences, family duties before they express true feelings.
It is been almost 200 episodes and we are witnessing an intense non physical romantic relationship. For that Kudos to Krushal mainly followed by Heeba.