Eubanks was born on October 7, 1981. When he was 11, his father, an engineer, moved the family from a small town in Oklahoma to Denver. After struggling to fit in at a larger school, Eubanks' parents allowed him to attend Columbine High School out of district. He met his friend Corey DePooter at the end of their freshman year. At age 17, Eubanks was in the library at Columbine High School on April 20, 1999, when Eric Harris and Dylan Klebold entered. Klebold shot him in his hand and knee before killing DePooter. DePooter was under the same table as Eubanks at the time and Eubanks witnessed his death. Jennifer Doyle, who hid with Eubanks and DePooter, was also injured. Harris and Klebold soon after left the library and, fearing that they would return, Eubanks and other survivors fled through the library's emergency exit. Harris and Klebold would go on to kill 12 students and one teacher, injure 24 others and then take their own lives. Eubanks did not return to Columbine High School after the shooting and was instead privately tutored at home three days a week until he graduated in 2000. Within weeks of the shooting, Eubanks developed an opioid addiction that continued into his twenties. In 2006, Eubanks recognized that he had developed tolerance for prescription medications of oxycodone (OxyContin), Adderall, and alprazolam (Xanax). He then began using cocaine, ecstasy, and alcohol. Starting in 2006, Eubanks entered residential treatment centers three times without success.