Somewhere in his heart, Ahaan has accepted his feelings for Ishqi and that is why he is making sure he doesn't become reason for breaking his best freind's wedding. After Ishqi's confession, he let his internal guards down but still has external on. When he told dadi "he is not someone who will melt if someone says they love him", Ishqi's confession was on his mind. It clearly shows how that has melted his heart already. While getting ready, he remembered Ishqi's sweet gesture of kaleerein which makes him feel that Ishqi is the right girl for him but still due to circumstances he has to let her go. He knows she is the right girl for him, he knows he loves her and he also knows she has feelings for him. He could easily confess and win her for himself. So Ahaan is the real one who is "Sacrificing".
Ishqi is still unaware of her feelings and has not given it a name. Kartik keeps bringing 'love' word with Ahaan but nobody has confronted Ishqi. She also feels a deep connection with Ahaan where she senses his pain. Their eyes speak a lot. She always notices his tears, be it during Jagrata or other day when she herself was crying. She relies on him greatly and knows he will be the one who will stand by her always (their car confession). She trusts him and understands him much more than his family. Sonu thinks his bhai will blame her and disown her but Ishqi knows his bhai can be traditional but he does what is right.