The 24-year-old was sentenced to three years and nine months last year for aggravated arson after being found guilty of deliberately causing €1.5 million worth of damage to his Munich villa by starting a fire in 2011.
After serving 13 months in prison the Brazilian was allowed to return to Bayern and coach the club's Under-23 side on while on day release, but he has admitted the last year has been the toughest of his life."I'm feeling better now, but those first 13 months in prison were incredibly hard," he told TV Globo.
"I cried a lot when I received the first letters from my wife in jail and saw the pictures of my children. I went to the toilet so that my cellmate couldn't see how much I was crying.
"I will do absolutely anything for my wife and kids."
Breno also opened up about the most dramatic moment since being sent to prison, when another inmate attempted to commit suicide.
"I was there when one of the prisoners tried to kill himself. He has a maximum sentence and tried to take his own life rather than serving his time."