Does anyone know this book.

This is a bit of a long shot, but the John Wyndham thread made me recall a book I read in high school (about 20 years ago - eek!). I remember finding it quite interesting, but I can’t remember the title or the author.

It was a sci-fi post apocalyptic story, sort of like The Stand. If I recall correctly, it centered around a young girl, who was messiah-like but horribly disfigured by radiation, as were several other people, including the villain (or so it appeared throughout most of the book). As it turns out, the disfigurement is like a temporary mask, which eventually falls away and face revealed reflects the person’s inner beauty, or lack thereof. Of course, the little girl is angelically beautiful and the villain is indescribably hideous.

Can anyone help me out?

Swan Song by Robert Mccammon

Thank you!