Have you ever believed something silly that, in retrospect, was really embarrassing? Here's mine:

The first several times I heard the song Glycerine, I heard it wrong and I thought it was the weirdest radio ad for Listerine I'd ever heard.

Give us your embarrassing truths, GT!

ETA: Btw, InfectiousGirl was 22 before she found out that "I Saw Mommy Kissing Santa Claus" was not about mommy kissing the ACTUAL Santa Claus, when she made a comment to that effect and her father and I both looked at her in "wait...you're not serious?"-level confusion.