Bach's body was found Saturday near Portage, Ind. Her friend, Dustin McCowan, 18, has been charged with murder and is being held without bail.
Bach's friends and family attended the Friday morning service at the Nativity of Our Savior Catholic church in Portage to celebrate her life, they said.
The 19-year-old was shot to death. Her body was found 300 yards from McCowan's Valparaiso home. This week, investigators searched the area for DNA evidence.
"We prefer not to dwell on that issue today, given that Amanda is at peace and really we're trying to focus on her life," Dr. Carlos Cespedes, Bach's uncle, said.
Friday morning at Bach's funeral, her friends were still in disbelief. They want people to remember her shining personality.
"She was so bright," said friend Melissa Fredenrich. "Our family loved her. Her friends loved her. We'll never forget her. She will always be a huge part of my life."
"She lights up a room with her smile," said friend Alyssa Boglin. "Her laugh is contagious."
"It's sad," said friend Bernadette Parish. "I feel sorry for her parents. They have to go the rest of their lives."
"She was a great person. She doesn't deserve the way she died," said Allyson Edwards.
Classmate Alexys Taylor spoke up for her when bullies picked on Taylor in school.
"I would like people to remember her as a nice person who would do anything to help other people. She was an angel from the Lord," Taylor said.
Bach had recently graduated high school and had been working as a hostess at a local restaurant. Her friends and family say she loved going to the beach and being with her loved ones.