Katrina is so beautiful, she's almost perfect. She only has two flaws. She's possessive. And she's dead.
William adores Katrina, but he almost forgets about her when he meets Adelle, with her gentle smile and winsome ways. So what's he to do? He certainly can't be faithful to a dead girl.
Even though he loves her, so much so he visits her grave every day. Even though she haunts him and constantly reminds him of the terrible thing he did.
Even though she might just drive him to do something terrible again. Very soon.