A question to all occultists

I remember once during a visit to my father's place long ago in my childhood, I was looking into the freezer for some ice cream, it was a hot summer day and I found a folded letter. It was in Spanish, addressed to my mother, it appeared scornful and hateful...So my question is...is this some form of dark magic? Writing a letter and putting it on the freezer? What purpose does it serve?