SALT LAKE CITY (RNS) For years, Matt Duff was an uber-Mormon.

At 17, he ran away from home and moved in with the only black Latter-day Saints family in his New England town.

Two weeks shy of his 18th birthday, he joined the Utah-based Church of Jesus Christ of Latter-day Saints.

By 19, he was on a Mormon mission in Denver, and two years later he enrolled at Brigham Young University-Idaho, where he met his future wife, Kylee, a multigenerational Mormon with a winning smile and a guileless faith. The two married in the Salt Lake LDS Temple.

Eight years and three children later, Matt Duff stopped believing.

"I suddenly didn't think faith was a virtue," he says. "I stopped thinking God would require me to have it."

Kylee Duff was shocked and dismayed. The church-dominated future she had imagined for them vanished. He wanted to talk of his reasons; she wanted him to shut up about them.

"The first couple of weeks were hard," says Kylee Duff, cradling a fourth baby, born after the crisis. "We were both pushing the other one to do what we wanted."

Yet in the year since their religious conflict erupted, the couple have done something remarkable: They continued to love each other.

Many other partners either split up or continue their holy wars. Often, the believer eventually follows the nonbelieving spouse out the church door.

In a 2012 nonscientific online survey of 600 LDS couples with at least one nonbeliever, Utahn Greg Rockwell found that, of respondents in which only one spouse had left the church, 26 percent reported that they had divorced, were divorcing or were separated. Forty percent said they were still together but experiencing marital tension.

"In other words," Rockwell writes in an email, "roughly two-thirds of respondents reported less-than-optimal marriage status post faith crisis."

There's a Facebook page, "Former Mormons with Believing Spouses," to help couples navigate these forks in the religious road.

Such statistics are not surprising, given the consequences these couples face, separately and together.

The believer can lose status in the church community, moving from an insider position of respect and possible leadership to a person of pity and concern.

The nonbeliever becomes an outsider, the subject of endless hand-wringing and proselytizing efforts.

The believer may feel angry that the spouse has now changed the rules they were living by; the unbeliever could feel equally miffed at being deceived by religion in the first place.

If they are parents, everything about their marriage and child-rearing will have to be renegotiated: Will their children be baptized? Will they still have daily prayers and scripture reading at home? How much information can the unbeliever share with the kids?

It's not easy to talk publicly or even privately about such problems in your relationship, especially in Mormon-dominated Utah. The Salt Lake Tribune interviewed more than a dozen people, but only a handful were willing to use their real names. Worried about reactions from family members, neighbors and co-workers who might judge, criticize or reject them, such people either seek comfort in private conversations or suffer in isolation.

Ardean Watts still remembers the February 1974 day when he stopped believing. It was an "aha" moment akin to a religious conversion, just in the other direction. He felt free, no longer having to "play the game," the 84-year-old Watts says now.

Watts, who was then on the general board of the LDS church's Young Men's program, didn't feel angry or betrayed by the faith that he had loved and served his whole life. He just felt "permission to move on."

It took several months for him to articulate the change to his wife and a decade of church activity before he stopped attending services. All the while, Watts and his wife continued in their marriage and reared their eight children in the Utah-based Church of Jesus Christ of Latter-day Saints.

"We didn't want to give up each other and neither of us drew a line in the sand," says Watts, a pianist and conductor who spent decades as a professor of music at the University of Utah. "I had no desire to recruit people to how I was thinking."

He attended all church-related events with his family, but had to have "that long talk about why Dad wouldn't be there" when a child would enter a Mormon temple for missions or marriage.

The key principle, Watts says, "is to tread gently."

Such mutual respect is a common ingredient in all successful marriages, of course, but even more crucial for those couples whose faith moves in opposite directions.

For many churches, a spouse's loss of faith may not pose a problem, but they worry about the children.

"You don't get to control your spouse, to decide whether or not he's going to Mass or how he's going to spend Sunday morning, but you do make joint decisions about your children," the Rev. Bob Bussen tells Catholic couples in Cedar City, Utah.

"If a couple marries in the church and promises to raise kids in it, that doesn't mean they have to remain Catholic, but they don't have a right to mess with their children's identity."

Many former members assert that Mormon leaders pushed their believing spouse to divorce them, and while that may be true in individual cases, it is far from church policy.

"No priesthood officer is to counsel a person whom to marry. Nor should he counsel a person to divorce his or her spouse," says the church's Handbook for LDS leaders. "Those decisions must originate and remain with the individual."

Whether couples stay together or part ways, they likely will experience the various stages of grief: denial, anger, bargaining, depression and acceptance, according to John Dehlin, a Mormon activist who is studying marriage and family therapy at Utah State University. "There's no clean way to get through this marital mess."

Kylee Duff said she prayed for her husband to come back to the Mormon church. "But I got the answer back -- that's not what he needs right now."

Matt Duff is doing "what he feels is right. I wouldn't want him coming to church if he felt it was wrong," she says. "He is still a caring husband and father."

God, Kylee Duff believes, will reward her husband for that.

During most of their decades-long marriage, Myndee Garrett threatened her husband, Randy, with divorce if he strayed from Mormonism.

She came from a strict LDS family and always felt guilty about their initial seesawing church activity. She blamed Randy Garrett, whose family was much looser about such things.

For 14 years or so, the couple reared their eight children in the faith and seemed to have weathered the worst.

In April, Myndee Garrett was the one who wanted out. She discovered troubling aspects of Mormon history and stopped believing. To her amazement, Randy Garrett did not want to leave her -- or the church.

"It blew my mind that he was so accepting of me," she says. "He's not black and white in his beliefs and never has been."

Though shocked by his wife's apostasy, Randy Garrett never gave divorce a thought. They had their ninth child after she lost her faith. He went without her to their eldest son's temple wedding and most Sundays goes to church services alone.

"Religion is a portion of who you are; it's not everything," said Randy Garrett. "Myndee's an amazing wife and mother who does such a great job with the kids and is just a great person. We have a big, noisy, loving family."

Things, he says, have a way of working out -- here and in heaven.

(Peggy Fletcher Stack writes for The Salt Lake Tribune).

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