"My angel, my best friend, the love of my life, my husband went to be with the Lord our God today," Katie Donovan wrote on Facebook

By Caitlin Keating
September 21, 2016 01:00 PM

Services are being held Wednesday for Dalton Prager, the 25-year-old who died of cystic fibrosis on Saturday before getting to see his wife, Katie Prager, whose own illness caused her to enter hospice care earlier this month.

The funeral service took place at 10 a.m. at Pitzman Funeral Home in Wentzville, Missouri, according to the St. Louis South-Dispatch.

The couple met online in 2009, when Katie sent Dalton a Facebook message to connect about their shared disease.

Like the star-crossed young cancer patients in the best-selling novel and 2014 film The Fault in Our Stars, they became inseparable, fell in love and took advantage of every moment they had together.

Both had been born with cystic fibrosis, a genetic disease leading to thick buildup of mucus in the lungs and other organs that restricts and worsens the ability to breathe over time. Patients have a current average life expectancy of 40 years.

Katie and Dalton Prager
Prager Family

“I knew that there was a possibility that we would get sicker and something could happen,” Katie tells PEOPLE. “I just told Dalton I’d rather have somebody that I was totally in love with for five years, than be either lonely or not as happy with somebody for 20 years.”

Five months after Katie, then 18, first reached out to Dalton, 17, she left Kentucky to move in with him outside of St. Louis. Just one month after that, he proposed.

“I was just so happy,” she recalls.

Katie and Dalton Prager
Prager Family

After a few blissful years together, they both became very sick.

“We wanted to keep living, we wanted to keep traveling, we wanted to just keep being the married couple that we always wanted,” Katie tells PEOPLE.

They both entered the hospital in August 2014 to receive life-saving lung transplants.

Dalton never fully recovered from his surgery, developing lymphoma and moving back in with his parents.

While the two were incapable of caring for each other, they texted, talked on the phone and Skyped.

“They were complete soul mates, and he couldn’t imagine life without her,” says Renee Prager, Dalton’s mother.

Adds Katie: “We told each other we loved each other the first day we met in person. We just knew,” she says. “He understood everything about me. He knew what I was going through, and he was just my other half. And I knew it.”

The couple had last seen each other briefly, for only a few minutes, in Katie’s Kentucky hospital room on their anniversary in July. Soon after, Katie decided to leave the hospital and enter a hospice program.

“How am I supposed to watch my wife die?” Dalton asked his mom. “How am I supposed to see her in a casket? I’m supposed to go first.”

Memorial contributions can be made to the Cystic Fibrosis Foundation or to the Leukemia and Lymphoma Society in care of Pitman Funeral Home, P.O. Box 248, Wentzville, MO 63385.