A B.C. woman who survived seven weeks alone in the Nevada mountains wondered whether her husband might have died after setting out to seek help, according to notes she wrote during her ordeal.

Owyhee County Sheriff Daryl Crandall told CNN that notes written by Rita Chretien were found in the van where she was discovered on Friday.

"Please help. Stuck since Mar 19/11," Chretien wrote on the note in red lettering.

The next line of the note read: "No food. No gas. Dead bat. [battery] Lost my way." 

Then she wrote: "Al went to get help. Find Mountain City. Did not return!" The last words on the page were, "Maybe died along the way?"

Albert and Rita Chretien were travelling from their home in Penticton, B.C., to a trade show in Las Vegas in mid-March when their 2000 Chevrolet Astro ran into trouble on a logging road in Elko County.

Rita Chretien, 56, was rescued Friday after hunters spotted the couple's van. But her husband hasn't been seen since he left their van to look for help after they got stuck.

Husband set out with GPS

Albert Chretien, 59, took a global positioning system with him and told his wife he was going to try to find a state highway.

Scrawled between the lines of the note in blue lettering are the couple's name, where they were from, and their phone number. Also written down was the name and number of the couple's son and the date they were expected back home, CNN reported.

A second note with detailed GPS readings said the couple were unable to get cellular service, CNN reported.

On Monday, Rita Chretien, who is recovering at St. Luke's Magic Valley Medical Center in Twin Falls, Idaho, was upgraded to a regular diet, starting with yogurt and dairy products. the hospital said. She will have her choice of six small regular meals per day as she continues physical therapy.

"Her spirits are extremely high," said hospital spokesman Ken Dey said in a statement. "The medical team is watching her closely, but indicators of her recovery are very good."

She had survived on a tablespoon of trail mix, a single fish oil pill and one hard candy a day, her son, Raymond Chretien, said Sunday.

She reportedly lost as much as 30 pounds during the 49-day ordeal, and family members and doctors agree she faced the prospect of death had she waited much longer to be found.

Searchers acquired a GPS like the couple's in an effort to retrace the route Albert Chretien told his wife he hoped to take to the town of Mountain City, 26 kilometres from the Idaho border.

Rain and snow kept a search helicopter grounded Monday, but about 30 people continued the hunt on horses and ATVs.

Reliability of GPS questioned

Meanwhile, the reliability of GPS was once again in the spotlight. Police in Nevada said the Chretiens were likely led astray by their GPS.

Rex Turner, a GPS engineer based in Oklahoma, said there is no denying the benefits of the product  when driving in an established city.

But he said the farther you get out of town, the less reliable the systems' maps become.

"Rural routes are worse, turn by turn data really breaks down out in the country," he said.

Turner said a GPS can't be 100 per cent reliable because it relies on information that is quickly changing.  

"Roads are constantly being worked on, neighbourhoods are constantly being built and you're at the mercy of government maps that are quite often old," he said.

MAP: a B.C. couple's perilous journey
With files from The Associated Press and Canadian Press