A new family crisis has Jessica Simpson reeling – her beloved grandmother has undergone lifesaving surgery to remove a tumor.

The 29-year-old  star is keeping vigil at her grandmother’s hospital bedside – and friends fear the ordeal could send the already emotionally fragile star over the edge.

"Jessica’s been a mess over her grandmother’s condition," a family friend told The ENQUIRER.
"She breaks down and cries a lot, and she keeps saying she feels like her world is crumbling."

Jessica’s maternal grandmother Dorothy Drew underwent surgery on Jan. 29 in Texas, and Jessica remained at the hospital with her mother throughout the procedure.

Jessica is very close to Dorothy, who appeared regularly on "Newlyweds," the MTV reality show Jessica did from 2002 to 2004 with her then-husband Nick Lachey.

"Dorothy has seen Jessica through her career ups and downs, and it was especially her Nana who was there for her when Jessica’s marriage crumbled. Jess just adores her," said the source.

Her 77-year-old grandmother’s surgery comes at an especially tough time for Jessica who, as The ENQUIRER has reported, recently suffered an emotional collapse after months of bad fortune.

The one-time red-hot singer/actress is desperate for a hit with her new VH1 reality show The Price of Beauty.

She’s been mercilessly ridiculed for her expanding waistline and fashion missteps, was dumped by Dallas Cowboys quarterback Tony Romo, and her dog Daisy was snatched by a coyote. Most recently, her fling with rocker Billy Corgan flamed out AND loudmouth ex John Mayer described sex with Jessica as "crazy" and "like crack cocaine".
"Jessica was really hopeful that the New Year would bring new beginnings and good luck, then doctors found her grandmother’s tumor," said the source.

 "It seems as if the poor thing can’t catch a break."