(CNN) -- Ingrid Case was a devoted church-goer as a child, not only attending Sunday school, but also serving as an acolyte at her Episcopalian church in Greeley, Colorado.

More than half of American adults have changed religion in their lives, according to a new survey.

"Basically, it's the priest's assistant," she explained. "You carry a cross in front of them, get the things they need to perform the service, scurrying around doing what they need."
But after college, Case drifted away. She didn't feel like she fit in socially at the Episcopalian church in Princeton, New Jersey, and found herself uncomfortable with some of its theology.
"I began to see there were some things I wasn't able to get on board with fully. I don't like the traditional Episcopalian focus on the afterlife," she said.
Today she's a Quaker.
She got involved with the Society of Friends, as the denomination is formally known, through the man who later became her husband, Nat Case. He wasn't raised a Quaker either, she said, though he went to a Quaker-run boarding school as a child.
Her shift in religion was gradual, said Case, 41, a freelance writer and editor in Minneapolis, Minnesota.
"It wasn't so much 'You people stink and I am out of here,' as 'I like this better and this is what I want to do.' "
Case isn't alone. More than half of American adults have changed religion in their lives, a huge new survey by the Pew Forum on Religion and Public Life found. And there is no discernible pattern to the change, just "a free for all," one of the lead researchers told CNN.