Casey Johnson seemed to have it all.
An heiress to the Johnson & Johnson fortune, she was the great-great granddaughter of the founder of the pharmaceutical giant and daughter of billionaire New York Jets owner Robert "Woody" Johnson. She counted among her friends, socialites Paris and Nicky Hilton and actress Lindsay Lohan, and she once dated Courtenay Semel, daughter of former Yahoo chief Terry Semel.
Yet, despite her wealth and connections, Johnson was arrested last December on burglary charges for allegedly stealing clothes and jewelry from a former friend. According to the New York Post, Johnson also lived a life of squalor, in a garbage-filled, rented house with no electricity, water or gas that boasted rats in the pool.
She and her girlfriend, D-list reality TV star Tila Tequila recently claimed they were engaged.
Tequila took to her Twitter account Wednesday to express her sorrow, tweeting, "I have 2 move out of this house asap! I cannot move on if I keep living here. Its just a huge dark reminder for me that shes not here NEmore"
"I had so many beautiful big surprises for her this year that she would have LOVED!," she continued. "But now my beautiful Wifey has left me @caseyjonsonJnJ =( ... We used to tweet each other @caseyjonsonJnJ while laying right next to each other in our bedroom. But now I tweet alone.. unbearable pain."
"I shouldn't be on the net but this is the only place I can find some temporary solace. I miss her so much. Sooooo much. Didn't get 2 say bye," Tequila concluded.
On Monday, the 30-year-old socialite's body was found in her Los Angeles home and there are reports that she may have been dead for several days. Police said Monday that Johnson appeared to have died of natural causes.
"Our officers conducted a preliminary investigation which appears to be an apparent natural death,'' Los Angeles Police Department spokeswoman Officer Sara Faden said." There was no evidence of any foul play and the case is now being handled by the coroners, pending a toxicology report.''
A spokesman for the Los Angeles coroner said Tuesday an autopsy could be performed by today, but final autopsy results are typically not available for several weeks.
Johnson leaves behind a 3-year-old daughter, Ava Monroe, whom she adopted in 2007 from Kazakhstan, who was reportedly not living with Johnson at the time of her death. She also leaves behind numerous questions about what went wrong for the woman who seemingly had it all.
"I don't know what happened," Lizzie Grubman, a New York publicist and friend of Johnson's since she was a teenager, told ABCNews.com. "She was an amazing girl with a huge heart, very funny and will be missed by me dearly. I was blessed to know her."
Grubman, who had spoken to Johnson about a month ago, said she saw no reason why Johnson would try to intentionally harm herself. "She was in great spirits. She had her daughter she loved dearly. She had great friends," she said.
Johnson had juvenile diabetes since childhood. "It was very serious," Grubman said. "She treated it with insulin. When she worked as an intern, she was embarrassed by it. She didn't want people to know. As she got older, she learned to deal with it."
In a recent red carpet appearance with Tequila, Johnson held up a syringe in front of the paparazzi and declared, "I'm diabetic."
Ken Baker, executive news editor for E! News, told ABCNews.com that Johnson's life was not what it appeared. In August, Johnson and then girlfriend Semel approached Baker about doing a reality show on their lives as a Hollywood lesbian couple.
"How strange, I thought, she was this heiress from one of the wealthiest families and wanted to be a reality star," Baker said. "There was something incongruous about that. What she made clear to me was that she was basically on her own.
"She was ready to put her daughter and her life on TV," Baker said. "She wanted to make her own family and her own life. She just really wanted to create a family. She felt she didn't have that for whatever reason."
Baker believes Johnson was estranged from her wealthy family, including mom Nancy Sale Frey Johnson, who was divorced from her father, and may have been cut off financially.
But Grubman said Johnson "loved her mother dearly and her parents loved her very, very much. I can only imagine they are devastated."
On Monday, the Johnson family released a statement, The Associated Press reported, saying it's "mourning its tragic loss, and asks for privacy during this very difficult time."
It's been reported that Johnson's mother had been taking care of Ava for some time. Johnson reportedly struggled with drug and alcohol addiction, though Grubman said she never saw it. When Grubman had dinner with Johnson, her former intern, three months ago, she said Johnson was "very sober. She was in great shape."
But a few days later, Johnson, according to media reports, returned to rehab. "People were worried about her," Baker said. "More than one person over the last couple years told me they were worried about her."
One person who was worried was former friend Jasmine Lennard, a model and British reality TV star. "I tried to get her off drugs and alcohol. I tried to get her into a 12-step program. I tried to help take care of her daughter and gave her money. I am the only person who helped this girl," Lennard told the New York Post's Page Six.
On Tuesday, Lennard said in a statement to ABCNews.com, "Casey was a classy, witty, beautiful lady, whom I loved deeply. My thoughts go out to her family, who have suffered such a terrible loss. I am completely devastated."
Last year Lennard was ready to get a restraining order against Johnson, who she says broke into her Hollywood home and took $22,000 worth of jewelry, underwear and other items. Johnson was arrested and released on $20,000 bail.
"I believe she was obsessed with me and thinks in her mind we had some kind of affair," Lennard told Page Six at the time. "That is not the case. She breaks into my apartment, gets into my bed, has a shower in my bathroom, then takes everything. I've had a hell of a lot of patience and compassion for this woman and she just hasn't treated me right. Casey is an evil girl."
Instead of the fame she sought, Johnson attracted infamy. While they were dating, Semel and Johnson had a nasty fight that ended with Johnson's hair reportedly catching fire.
Another time, Johnson started a public feud with her aunt Libet Johnson, when she accused her of seducing her then 38-year-old boyfriend, music manager John Dee. "An old woman with a lot of money is a very powerful aphrodisiac," Johnson told Page Six.
"My impression is she felt that she could be as big as Paris Hilton," Baker said. "She was like the real Paris Hilton but wasn't as famous as her."
Johnson and the Hilton sisters grew up together and Nicky Hilton was Ava's godmother. Paris expressed her sorrow over Johnson's death on her Twitter page Tuesday. "In bed crying, looking at baby pictures of Casey, Nicky and I. I feel so upset. I feel like I've lost a sister. My heart is broken," she wrote.
Hilton once asked Johnson to co-star on her reality show "The Simple Life." Johnson turned it down and Nicole Richie was cast instead. Baker believes Johnson regretted it.
"I remember her saying, 'People think I'm this crazy party girl, but I'm a mom, a single mom,'" Baker recalled. "She also recognized that she had a crazy life, bopping around from this house to that house. She appeared to me as someone who was unstable. She seemed to be her own worse enemy."
Johnson most recently made headlines in December when Tequila announced their engagement in an Internet video while sporting a 17-carat diamond and bragging "My baby is a billionaire." Tequila, who also dated Semel, appeared to be a recent addition to Johnson's life.
"When I spoke to her about a month ago, Tila was not in the picture," Grubman said.
Tequila may have been the last to see Johnson. The reality star told TMZ Monday evening that the two had fought last week and that she was unable to reach Johnson Dec. 29 after she left her dogs at Tequila's house. Tequila told TMZ that Johnson's phone had been turned off ever since.
"I can't stop these haunting visions of her and I," Tequila tweeted early Tuesday morning. "We made such a lovely couple, only beginning to spend the rest of our lives together..."