The 'Can't Fight The Moonlight' singer - who sought treatment for anxiety last year - is reportedly bracing herself ahead of the release of the 'Real Housewives of Beverly Hills' star's tell-all on February 13, which includes intimate details of LeAnn's affair with Brandi's then husband Eddie Cibrian in 2008, and is feeling very ''fragile''.
A source told Fox411's Pop Tarts column that the 30-year-old star has now read most of the book and is ''in a fragile condition'' and ''in a shocked state'' by how much she is featured in it, and how much Eddie and Brandi's two sons Mason, nine, and Jake, five, are as well.
The insider said: ''LeAnn needed to know what to expect from it all, and knew it would be bad. Perhaps just not that bad. She genuinely loves the two boys and has a great bond with them, which she obviously hopes never changes, in spite of everything.
''LeAnn has kind of been through the worst of it, but has a very strong support network around her for when things become too much. It's a slow road, but she is learning to rise above it and looking at the long-term priorities - her health, marriage and being a stepmom.
''LeAnn feels the need to always defend herself. But everyone is trying to stop her from engaging in it all.''
Brandi, 40, reveals in the book that she made Eddie buy her a ''new'' vagina after he cheated on her with his now wife LeAnn by using his credit card to pay for an intimate vaginal rejuvenation procedure, worth $12,000.
She explains: ''I would ask Eddie from time to time if my vagina was the same after childbirth. He always said yes, except once. He was actually quite vulgar.''
Since splitting from the 'Playboy Club' actor, the sharp-tongued blonde has been locked in a bitter war of words with LeAnn, who married Eddie in 2011 after legally separating from her husband Dean Sheremet.