Dreamers

Patrick has been having dreams of a girl, who he never met before, and he has a diary of his interactions with her.

One day a crow steals his diary, but leaves a notebook similar to his.
The owner of the other book is Susan and the entries are similar to his, but in her diary she has messages talking about his demise. Her regrets and how she is terrified of the thought of him. Why is she scared of Patrick?