Return to Eden (1983)

Rich but insecure heiress Stephanie Harper believes she's found true love with tennis pro Greg Marsden, but after the nuptials, Greg promptly begins an affair with Stephanie’s best friend, Jilly Stewart. Whilst on their honeymoon, Greg pushes Stephanie into a crocodile-infested swamp, and he and Jilly watch as she is apparently mauled to death. However, Stephanie miraculously survives and travels to an island clinic where she undergoes extensive plastic surgery. Using her new identity, Tara Welles, and fortune, she plots revenge on Greg and Jilly, aiming to take back what's rightfully hers.