Dugard, 31, spoke to ABC in advance of the release next week of her memoir "A Stolen Life."
She was rescued along with her two daughters in 2009, after 18 years in captivity, when her kidnapper Phillip Garrido aroused suspicion while proselytizing at a northern California university.
Dugard has since been reunited with the family that lost her in 1991, when Garrido abducted her at age 11. She lives with her mother and the two daughters Garrido fathered with Dugard when she was a teenager.
"Now I can walk in the next room and see my mom," Dugard told ABC News' Diane Sawyer in an interview to air on Sunday.
"Wow. I can decide to jump in the car and go to the beach with the girls," Dugard said. "Wow, it's unbelievable, truly."
Authorities say Garrido kept Dugard hidden for much of her ordeal in a squalid compound of tents and sheds behind his northern California home.
Garrido was sentenced to life in prison last month after pleading guilty earlier this year to kidnapping and multiple counts of sexual assault.
