I think the reason Cindy remembers all of the lies so well is because she has gone over and over this time in her mind for years now, trying to make sense of it all. She has been trying to find the truth in what she knows her daughter told her. She remembers every conversation and has dissected the conversations in her mind again and again to understand how she could be so duped.
I had three teens at once when my older kids were in highschool and believe me, they told me some whoppers that I believed at the time and couldn't believe I fell for them until I thought it through much later. You feel so foolish when that happens.