(CNN)November 11 was meant to be the day Intan Syari married her fiancé.
But her husband-to-be, Rio Nanda Pratama, was killed in late October when Lion Air Flight 610 crashed into the sea near Jakarta, Indonesia, soon after taking off.
On Sunday, which should have been the couple's happy day, Syari went ahead and took her wedding pictures alone -- fulfilling Pratama's final wish for her to do the shoot if he ever failed to return.
"Even though I feel grief that I cannot describe, I still have to smile for you," she wrote in the caption of a series of pictures shared on Instagram. "I cannot be sad but should be strong like you always told me to be."
Syari describes Pratama, who was a doctor, in older Instagram posts as her first love.
In the photographs shared on Instagram, Syari wears a white gown they had picked out before Pratama flew to Jakarta for a seminar, Ifan Deviandri, who works with Indra Permana, the photographer who shot the pictures, told CNN.
According to Deviandri, Pratama shared a "heartbreaking joke" with his fiancée before he left, asking her to wear a white kebaya, a traditional blouse, and hold a bouquet of "fresh white roses" and go ahead with the photo shoot if he failed to return.
"It was just a joke but unexpectedly it all happened," Permana told CNN, adding that Pratama "had long wanted me to be his wedding photographer."
He said the couple had known each other for 13 years, since middle school.
"I was confused as to how the pictures would look ... and how to deal with Intan [Syari]," Permana continued. "But thanks to the strength of her heart the photographs turned out well."
Some of the photographs Syari shared on Instagram include Pratama's sister, whom Syari said accompanied her on her fiancé's "last most beautiful request."
Pratama had taken the ill-fated flight which was heading to the couple's home city of Pangkal Pinang on October 29.
He was one of the 189 people on board who lost their lives.
Investigators who analyzed the jet's flight data recorder after the crash said there were problems with the air speed indicator on the past three flights before this incident.
More than three weeks after the crash, authorities are still searching for the plane's cockpit voice recorder, which is believed to be buried under deep mud. If found, it should reveal what happened in the cockpit in the final seconds of the flight.