(CNN) -- On a recent late night in New Jersey, Adam Robb sat up with Dulcie Laurance, lulling her back to sleep.
Robb's 92-year-old grandmother is one of an estimated 36 million people worldwide with dementia, according to 2010 data from Alzheimer's Disease International, and Robb is one of about 65.7 million people in the United States taking care of relatives with various conditions, including dementia.
"It's 11:45 p.m., you just went to bed," Robb wrote to her; Laurance has been deaf for 25 years and macular degeneration undermines her ability to read lips, so Robb, a journalist, communicates with her via written notes. Laurance smiled and sheepishly laughed.
Impairment in the body's internal clock, ultimately disrupting a person's sleep-wake cycle, is just one of the potential symptoms of dementia. When Laurance woke up that night, she'd misinterpreted a light in the living room as a sign that it was time to get up and start her day.
It hurt Robb to see his grandmother changing, but he stayed with her, knowing she once did the same for him.
Rethinking and adjusting relationships is one of the often overlooked parts of being a family caretaker, aging experts said. Since no two people experience dementia in the same way, many caregivers are at a loss with how to cope with a disease that can rob the vivacity and obvious connections of loved ones they once knew.
"You have to separate what your relationship was before," said Laura N. Gitlin, director of the Center for Innovative Care in Aging at Johns Hopkins University.
Dementia is a loss of brain function and affects memory, thinking, language, judgment and behavior. Alzheimer's disease is the most common and among the most severe types of dementia. Most aren't reversible.
"It's not merely a memory lapse -- we all have those moments where we forget somebody's name or we forget where we put our keys or glasses. This is really very different," Gitlin said. "You not only forget something, you then don't have a strategy of how to correct it."
Laurance was always kind, proud and "grandmotherly," Robb said. Memories of those characteristics drove his decision to move from his own Jersey City apartment in September 2011 and back to his mother's house -- they'd noticed that Laurance became more animated when her grandson was around.
She can still recognize her own home and who is with her -- usually Robb and his mother, who shares in caregiving responsibilities.
"I feel terrible when she just can't seem to put it together; that's the worst," Robb said.
Her dementia is on the tamer side of the spectrum; for many, it means forgetting precious relationships and people.
"The best you can give for a person with dementia is recognition of the person they were and are and be compassionate in your communication," said Darby Morhardt, a research associate professor at the Northwestern University Feinberg School of Medicine's Cognitive Neurology and Alzheimer's Disease Center.
Compassion includes caregivers recognizing what is and is not within their power to change as the relationships evolves. Correcting mistakes, essentially drawing attention to the memory loss, will likely lead to frustration and embarrassment that can lead to agitation and anger.
"Always remember to help the person with the illness 'save face,'" Morhardt said. "If the person thinks they're in a different city and it really makes no difference that they are told otherwise, it is best to not correct, but to connect on an emotional level."
She said they can sense the caregiver as someone they feel close to, whether or not they know the person's name.
"Enter the reality of the person with dementia and do not try to force them to enter yours," Morhardt said.
It's important to remember that the person isn't acting forgetful or difficult to hurt family members or caregivers, aging experts said, and they can still pick up on negative reactions, even if they don't understand why.
"People who do have dementia are extremely sensitive to the emotional tone set and they can pick up if someone's angry or disappointed," Gitlin said.
"It's important to understand that when the person does or says things inappropriate or negative, that it really is the disease process and that the person may be overwhelmed and you cannot put intention to that behavior you see."
Dementia sufferers are not able to take the feelings of others into account. They become uninhibited and say things that may have been fleeting thoughts in the past -- a "say what we're all thinking" mentality.
"Caregiving for a parent can bring up a lot of emotion -- parents know how to push our buttons and that does not stop with dementia," Morhardt said.
Ultimately, caregivers must accept it's the neurodegenerative disease talking, not past spites or misgivings.
"Spouses and adult children can be confused by the behavior of someone with dementia and think that what they are doing and saying is purposefully hurtful. It is important to recognize that it is the disease talking," Morhardt said.
It's also important to recognize that while it is a caregiver's duty to focus on another's health, it's imperative they focus on their own health as well.
"Primary doctors should be tracking caregivers not only because they're at a great risk for depression, but for other kinds of poor health outcomes," Gitlin said.
Resentment can ultimately overwhelm the desire to help.
The National Center on Caregiving estimates that 40% to 70% of caregivers have symptoms of depression, which can lead to more health problems. Spouses caring for a husband or wife are particularly likely to experience depression.
But with 65.7 million family caregivers -- 10 million of them caring for people with diagnosed dementia -- there's safety in numbers. Organizations like the Alzheimer's Association sponsor caregiver support groups throughout the nation.
"We all manage. We do what we need to do," Robb said.
Robb still remembers long weekend and holiday car rides, when his grandmother would sit beside him in the back seat and make up stories that stretched the entire trip. Now, his mother prints stories he writes for the Jersey Journal in extra-large print so his grandmother can read them.
"It makes me happy to see her enthusiasm for them, knowing they keep her as entertained or distracted or as happy as her stories made me," Robb said. "You never really know how or when or if ever you can pay back a family member for what they did in helping raise you, so I'm lucky to be able to experience and recognize this."
The relationship rewards might not be the same, but they still have value, experts said.
"Recognize your limitations and the limitations of others," Morhardt said. "Acknowledge the grief and sadness, but try to appreciate the moments of connection."
Those moments of connection still make lasting memories.