San Diego Sheriff's deputies said Fuller's boyfriend, Vidal Webb, poured flammable liquid over her body while she slept and then lit her on fire.
Co-worker Christen Hanley said Fuller is still in a medically induced coma at UC San Diego Medical Center and that the burns cover 75-80 percent of her body.
"I couldn't even fathom who could have done something to one of the nicest, warmest, friendliest, most positive, sweetest people that I have known," said Hanley.
As for Webb, deputies said he fled to a City Heights home and was arrested after a 10-hour standoff. Two days later, officials said he committed suicide in jail.
Around 80 friends of Fuller, who was an assistant to an equine veterinarian, donated $20 each to ride horses together Saturday. The funds will go towards Fuller's medical bills.
Many also took part in a silent auction. Some of those who couldn't donate money gave things that others could buy. Friends raised nearly $10,000.
"People do have a good heart, because people have come together and raised money for Lynn and shown just love and support and kindness," said Hanley.
Friends have also set up a fund for Fuller online.
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