In 2010, the couple left the islands to tour the mainland United States, bringing their message of returning to ancient values and putting more than 95,000 miles on a borrowed car.
The couple talk about the grandmothers' prophesy at bookstores and in people's homes, never taking money for their time and staying with locals.
"We are still living exactly as we did - a jar of peanut butter between us," said Miller.
They never know their next stop and rely on the "guidance" of the grandmothers -- and serendipity. "A Canadian couple was on vacation in the Island and took us to lunch," said Miller. "We get an address and someone flies us to Seattle."
They never solicit money for their work. "We are invited to someone's living room and a dozen people are there and put something in the donation bowl," Miller said. "What goes in the bowl is exactly enough to get to our next stop."
This summer their touring was interrupted when they were in a car wreck with a drunken driver in California. The car was destroyed and Miller suffered a concussion and broken ribs and a bruised lung.
She felt compassion for the man, who had just been released from prison -- and for the generosity of the community that pitched in to help her while she was hospitalized. "He went to jail at 31, the age of my oldest son," she said. "We all screw up."
Miller insists she is a rational person even though people get "freaked out and mad" when she says she hears voices. The grandmothers recently told the couple to stop sleeping on the beaches. Friends have loaned them places to stay and a car when they go back and forth from the mainland to Hawaii.
"There is nothing New Age about it," she said of the grandmothers' whispers. "I am simply telling my story, that's all. I am an old journalist -- the definition of a skeptic."
As for her youngest son who was taken along for his mother's adventure in austerity, he put himself through college. "There was no money," she said. In spite of the rough years, he graduated magna cum laude and is teaching English in Korea.
"This kid's a writer and some day he will write his version and it won't look anything like mine," said Miller. "He's told me I don't show enough remorse for what I put him through."
Still, Miller said her son has good memories of the sunrise and rainbows when they lived on the beach.
Miller said she has no regrets about her choice. "The truth is I feel happy and fulfilled," she said.
"My husband's experience was that he had an epiphany," she said. "I have never seen his faith shaken for a moment."
But for Miller, giving up her "stuff" for a more spiritual life was "an amazing transition for me, a sense that there is something more in this world."