11/18/2013 at 02:00 PM EST
is a changed woman.
Following her treatment
for addiction and other issues three years ago, the X Factor
mentor, 21, is releasing a book, Staying Strong 365 Days of the Year
, a collection of quotes and daily goals she hopes will help others. The book is out Tuesday.
One of the quotes, which she shared exclusively on Facebook
Monday, is the "Serenity Prayer."
"I have spoken this prayer almost every day of my recovery," she writes in the book, "and it has helped me simplify the sea of emotions and feelings that often run through me, especially on a hard day."
Adds Lovato, "We do the best we can in life, we take things one day at a time and sometimes we all just need a simple reminder of that."
The "Serenity Prayer" chapter of Staying Strong
corresponds with an important date.
"March 15 will always be an important day to me," Lovato explained on Facebook
. "It's the anniversary of the day I began my recovery. As I share a part of my life with you, I want to hear your stories, too. Comment below using #StayingStrong365 and tell me what helps you get through the hard days."
On Monday during a Good Morning America
interview, Lovato explained the format of her book.
"Over the past few years, I've done this thing – a morning meditation basically, where I read out of a book and it's a quote, a passage and then a goal for the day," Lovato said. "So basically what I wanted to do was do that for my fans. It's really cool. There [are] quotes in there all the way from Einstein and Aristotle, to Nicki Minaj and Tupac [Shakur]. It's crazy."