Turner, 72, revealed in an exclusive interview with People published on Wednesday that he was diagnosed with Waldenström's macroglobulinemia.
Waldenström's macroglobulinemia is a rare blood cancer that results in an excess of abnormal white blood cells in the bone marrow, according to the National Institute of Health.
The NIH estimates that the disease affects three in a million people per year in the United States and the condition occurs twice as often in men than women.
Turner told the outlet that there being no cure for Waldenström's macroglobulinemia "weighs heavily in every decision I make" and that the diagnosis "was like 10 tons of concrete were just dropped on me."
"And I was a bit in denial for a while, I didn't want to admit it," he told People.
All of this occurred while he was still married to Theresa Nist, whom he proposed to on "The Golden Bachelor," which aired its finale in November 2023, and whom he married in a televised wedding on ABC in January.
The couple revealed to "GMA" in April they were divorcing.
Speaking to People, Turner said that after his diagnosis, "the importance of finding the way with Theresa was still there, but it became less of a priority" compared to spending time with his family.
"When you are hit with that kind of news and the shock wears off after a few days or a few weeks and you regroup and you realize what's important to you, that's where you start to move forward," he told the outlet. "And I hope that people understand in retrospect now that that had a huge bearing on my decisions and I think probably Theresa's as well."
Turner said he's embracing the fun of life and not living with regrets these days and wishes Nist "all of the good luck in the world, that she finds everything she wants to" and holds their brief relationship as "a cherished memory."
In a separate interview with People, Nist said Turner's cancer diagnosis "didn't factor into ending the relationship" -- at least from her point of view.
"I wish him the best and that I know that he was in a very difficult situation and that good things will come to him," she told the outlet of her message for Turner. "And I wish for him a long and healthy, prosperous life, and I hope that he finds his person. I want him to be so happy, and I just wish him all the best of everything in the world."
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