Details of Disappearance
Diane was last seen at her home on Delaware Avenue in Nampa, Idaho on the morning of March 25, 1977. The previous day, she and Fred, her husband of two years, had gone to the library and checked out a book.
Fred asked Diane if she wanted to go for a walk afterwards, but she declined and said she didn't feel well, so they went home. The next morning, Diane still didn't feel well. Fred went to work at 7:20 a.m. When he returned, his wife was gone.
There were no indications of a struggle or forced entry to the home. The car was still parked at the residence and there was mail in the mailbox and a UPS package on the porch. All of Diane's belongings, including her purse and money, were left behind at home.
Diane's three cats were locked in the spare bedroom, which is where she normally left them whenever she went out, but she left her wedding ring and watch on top of a desk, which is where she kept them when she was at home or only going out for a few minutes.
Diane has never been heard from again. She has no history of dropping out of sight and she is described her as an extremely reserved woman who had no friends in the area, didn't associate with the neighbors and rarely left the house.
She enjoyed reading, macrame projects and spending time with her pet cats. She was estranged from her parents and the only person she was close to besides her husband was her grandmother, who lived in Flint, Michigan; they kept in touch by phone.
According to the Schultes' neighbors, Diane and Fred were devoted to each other and had no history of domestic arguments.
Diane's grandmother stated she was "highly upset and emotional" during their last conversation, possibly because her parents were coming to visit later that year. Diane didn't want to see them and had asked Fred to persuade them to cancel the trip. However, Fred stated his wife was in an "unusually good mood" just prior to her disappearance.
On April 1, a week after Diane vanished, police asked Fred to take a polygraph test about his wife's disappearance and he agreed. The test was scheduled for the following week, but on April 3, Fred's body was found inside his wife's dark blue 1975 Buick.
Fred had been driving northbound on Highway 95 at a high rate of speed when he shot himself in the head, and the car ran off the road and down an embankment.
He left behind two suicide notes. The first was a will. The second stated Diane "gave my life meaning and purpose" and "was everything I ever wanted and needed in a woman," and that he had given up hope that she would return home alive and he couldn't live without her. Neither of the notes indicated that Fred knew what had happened to her.
Police have not named Fred as a suspect in his wife's disappearance, but foul play is suspected in her case. It remains unsolved.