For the first time since entering prison, Teen Mom star Amber Portwood explains why she chose hard time over a court-mandated rehab program. “I thought I was gonna die,” Amber tells Dr. Drew Pinsky on the upcoming MTV special Amber Behind Bars.Now, the new issue of In Touch — on newsstands now — has the first look at her emotional interview, which airs Oct. 9 at 10 p.m. on MTV.After battling her drug addictions and anger management issues for four seasons of Teen Mom, Amber, 22, ultimately opted out of court-ordered rehab and began serving a five-year sentence at Indiana’s Rockville Correctional Facility on June 5. Why? “I wasn’t getting anything out of treatment,” she confesses. “I was still doing drugs.”The troubled mom to Leah, 3, admits that she wasn’t giving her daughter the life that she deserved. “[Leah] needs more,” Amber admits. “I just know that I can be better than I was.”Looking back, Amber tells Dr. Drew that she knew she hit rock bottom when nothing – not even her daughter – mattered. “I was very selfish and all I wanted was to find drugs so I didn’t have to withdrawal and I didn’t care about who was in my way,” Amber says. Now that she’s finally getting the help that she needs, Amber is hopeful for a second chance when she gets out. “I’ll actually be there for [Leah] this time and I'll be that mom that she wants.”For more information about Amber’s daily routine in jail and status with Leah’s father, Gary Shirley, tune into Amber Behind Bars: An MTV Special on Oct. 9 at 10 p.m. and check out the current issue of In Touch — on newsstands now!