Farrah Fawcett and Ryan O'Neal

Ryan O'Neal, the longtime partner of Farrah Fawcett, is opening up about his heartbreak over the actress' ongoing cancer battle for the first time.

"It's a love story. I just don't know how to play this one. I won't know this world without her," O'Neal told People. "Cancer is an insidious enemy."

The magazine said O'Neal was emotional and often teary-eyed throughout the interview, during which he revealed that Fawcett is now on bed rest and running out of treatment options. "The doctors see that she is comfortable," O'Neal said. "Farrah is on IVs, but some of that is for nourishment. The treatment has pretty much ended."

O'Neal said Fawcett's golden locks are gone, but that she still enjoys watching TV and visiting with close friends, including fellow Charlie's Angels stars Jaclyn Smith and Kate Jackson. Fawcett and O'Neal's son, Redmond, also recently visited while on temporary leave from jail. O'Neal said he has kept the full truth from both Fawcett and Redmond.

"Farrah doesn't know Redmond's in trouble," O'Neal said. "And Redmond is terrified for his mother. 'I don't want to be in jail and have some guard tell me she is gone,' he said to me. I told him, 'She's rebounding.' I lied to him. I lie to her. It's the best thing.

Fawcett's battle with the disease — which started as anal cancer and spread to other parts of her body, including her liver — will be broadcast on Farrah's Story, a two-hour NBC documentary on May 15. O'Neal said Fawcett just happened to take a camera with her to the doctor one day — the day she found out the cancer had returned, it turned out — but then decided to keep filming.

"Farrah was devastated," O'Neal said. "It was horrible, terrible news.... There were times I'd stop filming because I thought it was too personal and she said, 'This is what people go through with cancer. Film it.' So I would."

O'Neal said Fawcett's courage throughout the ordeal has been inspiring. "The news started to get darker and darker and darker," O'Neal said. "The hope started to fade. But not for Farrah. She continued fighting. There was always a courage there, and a quiet dignity. Farrah never changed. I fell in love with her all over again because of how she handled this.... Farrah has never, ever talked about how unfair it is."

Fawcett's fight, O'Neal said, is what keeps him grasping at hope, but he said he avoids thinking of the future without her. "I can't hear a song, I can't pass places that we were together, without being stabbed in the heart," he says. "A week ago Farrah said to me, 'Am I going to make it?' I said, 'Yes, you'll make it. And if you don't, I'll go with you."

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