"Brittany was an incredibly loving and passionate person and an artist to her core - she loved acting, singing, dancing, and performing," her family said in a statement.
"A bright light that lit the world is forever dimmed, but will live on in the hearts of those that Brittany touched," said the statement, released Thursday after she was buried at Forest Lawn Memorial Park, Hollywood Hills.
The intimate gathering was "very nice, very respectful," said longtime family friend Alex Ben Block, who eulogized Murphy.
Her husband, Simon Monjack, talked about their relationship and called the 32-year-old Murphy his best friend and soul mate. The two married in 2007.
Her closest friends and her cousin also recalled their favorite memories of her.
The service began in the afternoon and stretched on past dark. A Christian minister and a rabbi presided and guests sang "Amazing Grace" at the grave site.
Block said Murphy loved Christmas and that it was ironic that she was buried on Christmas Eve.
A small group of reporters and a few news vans waited outside the main gates of the cemetery, where luminaries such as Liberace, Bette Davis, Lucille Ball, Gene Autry and Freddie Prinze are buried.
Murphy died Sunday after collapsing at her Hollywood Hills home.
Authorities continue to investigate the death but do not suspect foul play. An autopsy performed Monday was inconclusive, and the coroner's office is awaiting results of toxicology and tissue tests before determining an official cause of death.
Murphy moved with her mother, Sharon, to Los Angeles when she was a teenager to pursue an acting career. She started out in sitcoms and commercials in the early 1990s before winning starring roles in several films.
Her breakthrough role came in 1995, as a dowdy high school student (and best friend of star Alicia Silverstone) in "Clueless."
Murphy worked steadily after that. She shared the screen with Winona Ryder and Angelina Jolie in 1999's "Girl, Interrupted." She played Eminem's love interest in "8 Mile" and Ashton Kutcher's wife in "Just Married." She starred as a suspicious girlfriend in 2004's "Little Black Book" and a barmaid with an abusive ex-boyfriend in 2005's "Sin City." She also voiced Gloria the penguin in the 2006 animated film "Happy Feet."
Murphy was juggling multiple movie projects in the months before her unexpected death, wrapping two indie thrillers over the summer and preparing to shoot a romantic comedy next month.
Michael Feifer, who directed Murphy in her final role, described the actress as professional, kind and healthy on the set of "Abandoned." Monjack accompanied her on set and served as her hair and makeup artist.
"The two of them really took care of each other," Feifer recalled. "He was her teddy bear, and she was just his little princess."
The future of that film and Murphy's other thriller, "Something Wicked," is uncertain. Neither has secured theatrical distribution.
AP Entertainment Writer Anthony McCartney contributed to this report.