Silsila (1981)

Amit (Amitabh Bachchan) decides to bury his past life along with his love for Chandni (Rekha) when he meets Shobha (Jaya Bachchan). Shobha's life has come to a standstill after her fiancé and Amit's brother Shekhar (Shashi Kapoor) dies in a crash. When fate brings Amit and Chandni face to face again, both are married to different people - but neither can ignore their feelings for each other. —Official Source