(LifeWire) -- Joan Gershman, 59, does not mince words when describing how Alzheimer's disease has affected her marriage.
Lucy Bennett says her husband, David, feels free to express affection for women at his adult day care center.
"For 34 years, we were partners, lovers, friends -- and all of sudden I am living with a monster," she said of her husband, Sid, 65, who was diagnosed in 2005.
But the marital problems of the Port St. Lucie, Florida-based couple began years earlier.
"He became irrational; he was throwing temper tantrums; he couldn't be reasoned with," Gershman recalled. "It was like living with a stranger."
Alzheimer's disease, a progressive brain disorder characterized by loss of memory and language skills, afflicts 5 million people in the United States, according to the Alzheimer's Association, a nonprofit organization in Chicago, Illinois.
But the disease also affects partners of the sufferers.
Marriages can deteriorate long before a diagnosis, said Peggy Noel, founder of MemoryCare, a holistic-care organization in Asheville, North Carolina, that helps those with dementia. Marital problems arise partly because changes can be subtle and difficult to detect early on in the disease.
Few early diagnoses
At first, a spouse often grows resentful that "the patient is being obstinate, lazy, uncooperative or purposely difficult," Noel said. "There is almost always an 'aha' moment of recognition that a serious problem is present, but this is usually preceded by two to three years of subtle functional changes."
Many of these spouses said it would have been easier for them with an earlier diagnosis.
Dr. Ron Adelman, New York Presbyterian Hospital's co-chief of geriatrics medicine and gerontology, said he agrees.
"If you expect someone to do what they can't do, it creates a level of stress that could be dealt with if you knew the disease better," Adelman said.
Adella Harding, 62, of Gladewater, Texas, said she had such an experience with her husband, Dean, who was diagnosed two years ago at age 60.
"Our marriage suffered because I couldn't figure out what was happening to him," Harding said. "I was becoming a shrew, and he was lazy. He couldn't grasp what I was saying."
Adelman suggests that families educate themselves about the disease. If they suspect dementia, a geriatrician, neurologist or psychologist can do specialized testing to detect problems that may not be obvious in a brief visit to the family doctor.
Even with an understanding of the disease, spouses can be frightened by its effects.
"I know my husband is a victim of Alzheimer's," Harding said, but "it still hurt when he shadowed me everywhere or accused me of sleeping with some guy down the road I have never met."
She said she also worries about her husband's safety when he wanders. Since he's 5 feet 10 inches tall and weighs 260 pounds, people may not be as sympathetic as they would if he were "a frail 80-year-old with her bonnet on backward," she said.
For Gershman, keeping it all inside took its toll. People in her support group rarely spoke about Alzheimer's emotional effect on marriages, so she started the Web site thealzheimerspouse.com. An average of 750 people visit the site each day, and she has heard from spouses around the world.
"I was ashamed and guilty because I was really not liking this person I was living with," Gershman said, adding that the online community, where people feel more free to discuss feelings and their sex lives, helped her see she wasn't alone.
One of the more difficult challenges may be the effect the disease has on a couple's emotional and physical bond as a spouse's role changes from partner to caregiver.
Gershman recalled comments on her blog such as how hard it is to maintain sexual feelings for a spouse when you're cleaning dirty diapers.
Some men on the site have posted that they worry about scaring or hurting their wives, who now seem like children.
Lucy Bennett, 65, of Asheville, North Carolina, said she and her husband, David, 72, have made love a handful of times in the past few years.
"I've seen him be physical with women at the day care center," she said. "He loves to dance. His need for physical closeness is very much alive -- he just needs not to direct it at me all the time. It's hard."
It is not unusual for Alzheimer's patients in a nursing home or day program to enter into a new romantic "relationship." This phenomenon received a burst of publicity last year when it was reported that retired Supreme Court Justice Sandra Day O'Connor's husband, John, had become attached to a woman in the Phoenix, Arizona, facility where he lives. John O'Connor, a former lawyer, was diagnosed with Alzheimer's in 1990.
Coping with stress
And then there's the stress of caregiving.
"Add to the mix [that] they don't think you are the wife anymore, or that you are stealing from them or are cheating on them and you are up all night and you are sleep-deprived," said Laurel Coleman, a Maine geriatrician on the board of the Alzheimer's Association. "Those things make caregiving much more stressful."
Experts said every caregiver will experience stress, and they should have their own friends and hobbies to help them cope. Caregivers need to seek out -- and accept -- any help they can get from family, friends and community organizations.
Gerry Dudley, 76, of Hendersonville, North Carolina, said he found embracing his wife's diagnosis key to reducing his stress level.
"Acceptance and commitment. Without that, you are constantly battling it," he said.
"If there is any adjustment to be made, it is going to be [by] me, because she can't change."
Dudley said he is constantly adapting.
"It is not a journey," he said. "It's a dance." E-mail to a friend
LifeWire provides original and syndicated lifestyle content to Web publishers. Dr. Anna Loengard is a board-certified, Harvard-trained internist, geriatrician and palliative-medicine specialist, and an assistant clinical professor of geriatrics at the Mount Sinai School of Medicine in New York.
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