Daisy Coleman -- one of the teenage girls featured in "Audrie & Daisy," the Netflix documentary about multiple rape cases -- has died by suicide ... according to her mother.

Daisy's mom, Melinda, says her daughter took her own life Tuesday night. Her body was discovered after Melinda called the police to do a welfare check.

Melinda says ... "She was my best friend and amazing daughter. I think she had to make it seem like I could live without her. I can't. I wish I could have taken the pain from her!"



Daisy was 14 years old in January 2012 when she was allegedly raped at a Missouri house party after being plied with alcohol ... though no one was ever convicted.

The 2016 Netflix doc followed Daisy and members of her family as they dealt with the trauma of her alleged assault, and the hostile reaction of their community.

Daisy's mom says, "She never recovered from what those boys did to her and it's just not fair. My baby girl is gone." The family coped with another tragedy just last year when Daisy's younger brother was killed in a car accident.