Mrs Pelosi was woken up by Capitol Police pounding on the door of her Washington apartment at 5am on October 28.
She told CNN: “I was very scared. I’m thinking my children, my grandchildren. I never thought it would be Paul.”
On the eve of the midterm elections, the Democratic leader warned of rising threats of violence against lawmakers.
Paul Pelosi was bludgeoned with a hammer 11 days before the election by an intruder authorities said broke into the family’s San Francisco looking for the speaker.
He struck the 82-year-old in the head at least once.
The intruder told police he wanted to talk to Speaker Pelosi and would “break her kneecaps” as a lesson to other Democrats.
Mr Pelosi suffered a fractured skull and other injuries in what authorities said was an intentional political attack.
Mrs Pelosi said she was sleeping in her flat, having just returned from San Francisco, when there was a “bang, bang, bang, bang, bang” on her door.
“We didn’t even know where he was or what his condition was,” she said in excerpts of the interview scheduled to air on Monday.
“We just knew there was an assault on him in our home.”
David DePape, 42, is being held without bail after entering a not guilty plea to attempted murder and other charges. He also faces federal charges of attempted kidnapping of an elected official.
The fringe activist who followed conspiracy theories broke into the Pelosis home and demanded to talk to “Nancy”, authorities said.
When Mr Pelosi told him his wife was out of town, DePape said he would wait.
After the victim dialled 911, officers arrived to see the two men struggling over a hammer before DePape struck Mr Pelosi at least once in the head.
DePape later told police he wanted to kidnap the speaker and threatened to injure her “to show other members of Congress there were consequences to actions”.
The authorities’ stark narrative laid out in court filings in the case comes in contrast to the jokes and innuendo that conservatives and some Republican officials have spread about the Pelosis in the aftermath.
Mrs Pelosi has said little since the attack on her husband, cutting short her campaign appearances but spoke in a virtual call to grassroots activists late last week after he was released from the hospital.
“People say to me, ‘What can I do to make you feel better?’ I say: ‘Vote!’,” Pelosi told those on the call.
Her voice cracked at times as she said of her husband’s recovery: “It’s going to be a long haul.”