When Janet Stone lost half her life savings in the 2001 stock market crash and again in the national economic meltdown of 2008, she had enough with the banks and other financial institutions.

The 48-year-old San Francisco single mother and yoga instructor withdrew what was left of the nest egg she’d been stashing away in a bank since she was in her 20s, invested in a home safe and hid the key somewhere she thought no one would ever find.

But in a shocking twist, Stone went bust for a third time.

On Dec. 14, a burglar pried open the door of her home near Mount Davidson Park, broke into the trusty safe and swiped her life savings of more than six figures as well as jewelry and precious family heirlooms. Even the contents of her two young daughters’ piggy banks were stolen.

“I had been saving for over 20 years. I just crouched on the ground, put my head on the floor and cried,” Stone said. “I couldn’t believe that could happen.”

Despite the devastating loss, Stone said she looked around her ransacked home and was grateful that the thief left her Christmas tree intact.

The investigation of the crime is ongoing and, so far, no arrests have been made, said Officer Robert Rueca, a spokesman for the San Francisco Police Department.

There is no surveillance footage capturing the incident or witnesses, Rueca said, making it even more difficult to capture the bandit.

“It felt like they knew exactly where the safe was. It felt like they were in the house before,” Stone said, adding that she is very open with her home and often rents it out on Airbnb.

The burglar was able to find the key to the safe, which had been packed away in the back of a closet and zipped up in an “ancient purse,” Stone said.

She said she last pulled her money out of the bank in 2008 when she lost over half her savings in the national economic crisis.

She thought a home safe would better protect her earnings than a bank, but now, she said, she’s forced to rethink her ways.

“Anything that I was saving went into the safe,” said Stone, who lives with her 10-year-old and 13-year-old daughters. “We are just trying to make it. We don’t have a lot of cushion for later or if my kids get sick or if I get sick, so that’s really what that (money) was for.”

Unless the culprit or culprits are caught, that money will never be replaced, Stone said, adding that home insurance doesn’t cover cash.

In addition to losing the money, the burglar snatched her jewelry, including her grandmother’s diamond wedding ring, a family heirloom she’d been hoping to pass on to her children.

“That stuff was really sentimental, those things mean a lot. I don’t have photos of those things,” Stone said of the jewelry.

Stone has been a yoga instructor in San Francisco for 15 years and teaches classes at Yoga Tree, which has studios throughout the city. She also teaches workshops for yoga instructors around the world — including Bali, Indonesia, India and Australia.

Since the burglary, the yoga community has rallied around Stone, organizing a GoFundMe page. One yoga studio in Canada added a fundraising campaign to its classes to help Stone recoup some of her losses, said Connie Engel, who works as a training coordinator for Stone.

“When I first walked in and dropped to the floor, I lifted my head and was like, ‘That’s so unkind,’” Stone said. “But there’s been such an outpouring in the community and I just kept putting my attention on the kindness.”

Sarah Ravani is a San Francisco Chronicle staff writer. Email: sravani@sfchronicle.com Twitter: @SarRavani