In the Wizarding world, mail gets lost just as easily as in ours, maybe even more so. An owl may fall dead in its flight, or drop its mail in a particularly strong gust of wind. So all over the world there are letters and bills and small packages wrapped up in tree branches or stuck to eaves or melting to bits at the bottom of lakes. Usually the two parties involved in the exchange figure out the mail has gone missing, but sometimes, if they are out of touch with one another, they do not. That is how it came to pass that an envelope addressed to Lucius Malfoy from Hermione Granger was wedged under a loose shingle of a Muggle church halfway between their homes. Perhaps one day a roofer will find it, but that will only be once the minister has collected enough in the offertory to send one up, and by then it may have succumbed to the elements. So as it stands, we, and Hermione, are the only ones who know its contents:
Lucius,
I am sorry to have left you like that. You gave up your world for me, and I ran from it. But you're a smart man, and you know as well as I do that our relationship was never healthy, or built on anything other than feverish necessity. I did love you, but how long could I stay in that big house that once belonged to another woman? How long could I avoid looking Draco, my schoolmate, in the eye? I could not bear the idea of my friends out in the world, making something of themselves and wondering what had happened to me, the most promising of them all. Perhaps that makes me sound full of myself, but it is true.
I used to think very fondly of that awful little room, remembering our time in it together. Now I can only remember how cold it was, and how unbearably lonely when you weren't there. That is where I pictured myself dying, presuming that one day you would forget me.
Please don't think I have forgotten your kindness, because I truly have not. But soon I may. There is a therapist at St. Mungo's who helps people like me, people who have awful memories from the war. She's diametrically opposed to Oblivation as therapy, but she says that with her I can achieve some peace, and not be called to return to you anymore. It hurts to tell you that, but I believe that you will understand it's what's best. I really do hope that one day you will be able to forget me, too.
With care,
Hermione