Celine Dion and Rene Angelil's incredible and enduring 21-year love story

Celine Dion was known for her romantic hits like "My Heart Will Go On" and "Love Can Move Mountains," but her greatest love story was never in a song ... it was the one she shared with her husband, Rene Angelil.

The 47-year-old singer, who said goodbye to her husband on Thursday after his long battle with three bouts of cancer, showed unwavering love and support for her partner throughout his illness and even vowed to let him die in her arms.

Celine's bond with Rene started long before they were husband and wife. The French-Canadian singer met Rene when she was just 12 years old after she auditioned for him. At the time, he was 38 and was a music manager. "While I was singing he started to cry," Dion told PEOPLE years later. "I knew then I had done a good job."

Shortly after Rene became her manager and he became extremely invested in her success. At one point, he famously mortgaged his own house in order to pay for her first record. But as she later explained -- he believed in her talent.

From their wedding to 'Titanic' success, a look back at their love

The duo kept a purely professional relationship for years before going on their first official date. She was 19 years old and her first record, La Voix du bon Dieu, had already become a chart-topping success in her home province of Québec. Celine was still not a household name in the United States, but she was on her way to superstardom. Years later, she confessed that she saw Rene as more than her manager about a year before she was 19.

In 1990, Celine released her first U.S. album "Unison" and then the following year she received the American notoriety she had been looking for when she recorded the theme song to the Disney animation, "Beauty and the Beast." She and Rene became engaged the same year, however they kept their relationship out of the public eye.

"I was afraid of what people would think," she told PEOPLE of their relationship in 1994. "When you're in love, you want to scream it to the world," she explained

Despite their gaping age difference, the two fell in love and wed in a lavish ceremony in Montréal's Notre-Dame Basilica in December 1994. Celine stunned in massive white ball gown, a fur stole, and a beaded headpiece and veil.

"I'm not surprised that we married each other, because we have the same dreams," Celine said in 1995. "We have the same goals. We respect each other."

In 1997, Celine celebrated a massive year with the worldwide success of her song, "My Heart Will Go On" from "Titanic." She won an Oscar Award for her song, which was added to the pile of Grammys and other major awards she had won up to this point.

But 1998 brought one of the first major hardships in their marriage. Rene was diagnosed with throat cancer. Celine took a hiatus from her work and career to care for Rene. In 2000, the couple threw a lavish vow renewal ceremony in Las Vegas with an Arabian Nights theme in order to celebrate their love. And in 2001, after Celine underwent fertility treatments, the pair welcomed their first child together, son René Charles. The following year after a multi-year hiatus from music, Celine returned to the industry with her album "A New Day Has Come" and a five-year residency at Las Vegas' Caesar's Palace.

Throughout their time in Vegas, Celine and Rene remained committed and happy together. They regularly hit red carpet events together looking more loved up than ever. The couple expanded their family in 2010 after Celine became pregnant with twins. The cute kiddos were born in October and named Nelson and Eddy.

Despite the overwhelming joy over the past years, Rene's cancer returned in 2013 and Celine, again, took time away from the stage to care for her husband.

"I want to devote every ounce of my strength and energy to my husband's healing, and to do so, it's important for me to dedicate this time to him and to our children. I also want to apologize to all my fans everywhere, for inconveniencing them, and I thank them so much for their love and support," she said in a statement to ET in August 2014.

Celine briefly retuned to her show in 2015 and Rene's request for her to continue to share her talent with the world.

Throughout the ups and downs of their marriage, one thing always remained: He was in awe of her talent and so in love with her, and she so in love with him.