"Incomplete your promise was.. It was of holding my hand but not walking along through the journey..." . It was inspired by two songs. Tum Se Hi from Jab We Met, and Woh Humsafar Tha from the serial Humsafar. . The lines were "Aadha sa waada kabhi, Aadhe se zyada kabhi, Jee chahe karlu iss tarha wafaa ka" . And another line was "Woh humsafar tha Magar uss se humnawai na thi" . I've just somewhat merged them in my own way.