"It was a conversation that I didn't want to have with my parents," Te'o told Couric. "To say, 'Uh Mom, Dad, I missed my flight ... because I'm going to see Lennay in the hospital.' "
While she was in a coma at the hospital, Te'o said her relatives held a phone up to her ear and he talked. Nurses said the sound of his voice would cause her breath to quicken, and he'd hear the respirator and "the machines. It was very real."
She awoke from the coma, he said, as he was talking -- whispering his name and causing him to jump for joy, feeling he'd helped her.
"It goes back to what my parents taught me, to always be there for somebody when they need help," Te'o said.
There were more talks in the subsequent months, not just between the two but also involving Te'o's family. He said he was most hurt, most ashamed because the apparent hoax hurt not just him, but his father and mother.
"The belief in this person, the deception, wasn't only with Manti, it was our entire family," his mother, Ottilia Te'o, told Couric. "We had conversations with this person. So in our mind, we had followed the same pattern as Manti."
Te'o: 'I was just scared and I didn't know what to do'
Te'o said he was told that, on September 12, Kekua suddenly started to breathe hard, to sweat and, at 10:47 p.m., she died.
That was the same day his grandmother died. Three days later, he led the Fighting Irish to a 20-3 rout of Michigan State, saying he had been inspired to honor the two women with his play.
"I miss 'em, but I know that I'll see them again one day," he told ESPN at the time.
Even in death, Kekua continued to come up in interviews and elsewhere. She was part of Te'o's story.
Then came the December 6 phone call, from a woman he first thought was Kekua's sister. But then, he recalled, "She said, 'No Manti, it's Lennay.' "
"There was a long silent pause," Te'o said. "And I was angered to say the least."
Despite his renewed doubts, he kept talking -- including at the Heisman presentation on December 8, when he referred to his girlfriend losing her battle with cancer. A Twitter picture sent later that month showing the girl he thought was Kekua, holding a sign with that day's date, convinced him it was all a lie.
But he still didn't know what to do, or what to say.
"Part of me was saying if you say that she's alive, what would everybody think? What are you going to tell everybody who followed you, who you've inspired? What are you going to say?
He added: "I was scared. That's the truth. I was just scared, and I didn't know what to do."
On Christmas Day, he sat down with his parents in Hawaii.
Parents defend Te'o: 'He's not a liar, he's a kid'
This conversation led to one with Notre Dame coaches and administrators. But the school was mum until the Deadspin story came out.
That was followed by many stories as well as speculation about what happened and why. Did Te'o help concoct the hoax to promote his Heisman hopes? He said no. Did he help invent this relationship because he's gay? That, too, isn't true, he said.
It's uncertain how this scandal will affect his standing in the upcoming NFL Draft, set for April. Te'o said he's hoping for the best, though most disappointed in how he's hurt his family.
"The greatest joy in any child's life is to make your parents proud," he said. "The greatest pain is to know that they are experiencing pain because of you."
On the "Katie" show, his mother said she's proud of how her son has handled this entire situation -- saying that, in befriending who he thought was Kekua, he showed he "always puts others before himself."
His father said it's easy to spot the red flags in retrospect. But he said this ordeal hasn't rattled his faith in his son.