05/02/2011 AT 02:30 PM EDT
It's been just over a year since an affair cost him his marriage
to Sandra Bullock
and fallout from the scandal upended his world. "Everything got ripped to shreds," Jesse James tells PEOPLE in a candid interview, speaking from his home outside of Austin, Texas. "I was at my breaking point."
A 30-day stint at Sierra Tucson treatment center in Arizona not only helped James, 42, cope at the height of the crisis but, as he writes in a new memoir, American Outlaw
, it also shed light on his abusive childhood and turbulent life marked by anger and shame.
"I always felt out of place my whole life," says James, who still felt unworthy despite rising to fame and success as CEO of West Coast Choppers custom motorcycle outfit and host of Discovery Channel's Monster Garage
. "I never felt successful, never felt I deserved anything."
Although James takes "full accountability" for his betrayal of Bullock, he isn't dwelling on past mistakes. "I'm moving forward
, thinking clearly and becoming a better person. ... I have started life over."
James, who recently shut down WCC and relocated his family and work to rural Texas, says, "I've made my world pretty small. Now I can focus on what's important: making sure [my] kids get good grades and are happy and healthy."
One topic too painful to include in the memoir? Louis, the adopted son
James and Bullock had been raising together in secret before the scandal broke. "Talking about Louis almost felt too intimate," says James. "He is so sweet and I miss him."
For an exclusive excerpt of
American Outlaw and at-home interview with Jesse James, pick up the latest issue of PEOPLE, on newsstands now