Ahil is although blind by tanveer lies but he understands that love is not meant to be with the person u love but to be happy in ur love happiness. For example ahil did not even try to come close to sanam or confess his love to sanam because he thinks that sanam loves rehaan and she belong to him. She is his but not entirely his.
Rehaan on the other hand knows the truth of his mother but wants sanam in his life as his wife. He is waiting for the three months to end just to get married to her.
If i missed out on anything please do share would love to read ur comments.