Your being angry is welcome!
What was the supposed relation of the perp towards you?
Was there something about your experiences in the letter, that your man didn't know? how did/does he react? How is that for you?
I remember two key guidlines with best chances concerning stalkers:
Tell once clearly to stop.
Don't give the stalker any attention.
Anything you pay attention to, will grow.
- Who has told you, that you are anything but wonderful?