South Africans saw her swimming in the ocean and watching people jump off a cliff and into the sea, shaking her head as they leaped.
The country was rocked Thursday when news broke of Steenkamp's shooting death at the upscale house of the Olympic star and double-amputee athlete. Pistorius was arrested and charged with her murder and remains in custody in a police station.
Steenkamp's family said earlier Saturday that they had not been contacted by either the SABC South Africa's national broadcaster or the show's producers for permission to air it, but were not opposed to it because Reeva wanted everyone to see it.
"Her last words to us personally was that she wants us to watch it," Sharon Steenkamp said, hours before the program was shown.
SABC aired the reality show on its main channel, which prominently featured Steenkamp.
The show's executive producer, Samantha Moon, said going ahead with the show "is what she would have wanted."
Steenkamp, a 29-year-old blonde model who graduated from law school, died after suffering four gunshot wounds, police said. Officers recovered a 9 mm pistol from Pistorius' house and quickly charged the Olympian with murder over Steenkamp's killing.
Pistorius will appear in court Tuesday for a bail hearing, something police have said they oppose. Prosecutors also say they will pursue upgraded charges of premeditated murder against him, which means the disabled icon and double-amputee runner could face a life sentence.
Steenkamp is known in South Africa for appearing in commercials and as a bikini-clad model in men's magazines.
Pistorius and Steenkamp met Nov. 4 at the Kyalami race track, which sits between Pretoria and Johannesburg and has been used for Grand Prix and Formula 1 races, said Justin Divaris, a mutual friend.
Divaris said his own girlfriend was a close friend to Steenkamp. The two immediately hit it off and decided in the spur of the moment to attend a sports award ceremony together the same night, Divaris said. At the time, Pistorius had been dating another woman and his personal life was constant fodder for gossip pages.
Later, however, problems may have started, as police have said there were previous domestic altercations at Pretorius' home in a gated community near South Africa's capital, Pretoria.
A Steenkamp family spokesman said late Friday that relatives still faced a long struggle to come to terms with her killing.
"I can't see the family getting over this shortly," Reeva's uncle, Mike Steenkamp said. "It's going to be a long, long-term reconciliation with a lot of things and issues."
Family members plan for a memorial service next week for the model in Port Elizabeth, her hometown on South Africa's southern coast. Pistorius has a court appearance scheduled in Pretoria next week for his lawyers to argue that he can be released on bail.
Portions released earlier Saturday of the reality show, sponsored by a milk fruit drink, feature Steenkamp laughing and smiling on the beaches of Jamaica. Another portion shows her swimming with two dolphins, which tap her on the cheek with their snouts.
"I think the way that you go out, not just your journey in life, but the way that you go out and the way you make your exit is so important," Steenkamp says in the video. "You either made an impact in a positive or a negative way, but just maintain integrity and maintain class and just remain true to yourself.
"I'm going to miss you all so much and I love you very, very much."
Associated Press writer Jon Gambrell contributed to this report.
Gerald Imray can be reached at www.twitter.com/jongambrellAP .