Her eyes stared in listless reverie at the tiled floor of her room as a nursing assistant stopped in to empty the wastebasket. He chatted brightly with the silent woman as he straightened the bed; her glance never left the floor. Refilling her water pitcher, he left the room, saying he'd be back to bring her to dinner in an hour.

Her daughter Anne, my girlfriend, released the gentle grasp she had on her mother's hand, and fumbled inside her purse for the CD she had brought with her: a collection of songs that she and her mother had listened to years ago while making the weekly two-hour drive from the Twin Cities to Anne's father's home in St. Cloud, Minnesota.

This was the second time I had met Anne's mother, Roxie. The first was the previous weekend when she, her daughter and I had dinner together in the cafeteria of the nursing home. Anne inserted the disc and the old woman's eyes sparkled as the music began.

"Dale!" She smiled, looking directly at me. "Dale, you always had such funny hair!"

I had learned the weekend before that "Dale" was the name of Roxie's brother, who had passed away in 2007. Anne told me that in her more lucid moments her mother often mistook people for loved ones from her past. She encouraged me to go along with it, as there was no changing Roxie's mind, and it seemed to please Roxie that her brother had come to visit.Read about a wife who allowed her sick husband to believe he was having an affair

"Hi Roxie, I love your hair today!" I smiled back, not exactly sure what to say.

Roxie shot a surprised glance at her daughter, her eyes wide as if I had just said something terribly funny. Brushing a wayward strand of hair back behind her ear, her gaze slowly fell back to the floor, stopping when it reached the green tile she had been studying earlier.

This was how visits with Roxie went: sudden bursts of recollection or random observations dotting long periods of silence. Anne took it all in stride. She knew the prognosis, and she made the 45-mile trip to the home every weekend and most Wednesdays. As the only child of divorced parents, she felt that it was her duty to visit her mother as often as she could.

Until I met Roxie I had only a passing knowledge of Alzheimer's disease. I thought it was simply forgetting people's names, eventually no longer recognizing their faces. I had no idea how painful it was to watch a loved one's personality evaporate, to watch as shared memories and experiences disappear until there's nothing left to do but accept it, to smile when you are mistaken for someone from the past, thankful even for that hint of memory. In all the time I was there Roxie never called Anne by her name, although there was always a flash of recognition when she heard her daughter's voice.