Letters To A Secret Admirer

I have an admirer. It all started when my mom had enough of my moping about my love life or lack of. She was crazy when she said said send a love letter to some random address and say its from an admirer. What I didn't expect is for the person to write back within a week of the letter! They always write and send me a letter every month at the same day the 14 when Valentine Day was set on and the day the 1st letter appeared. I feel I know the admirer from the letters I've not wrote back but that doesn't stop the letters coming from the address I sent the first letter. So I wait from my monthly letter that's bound to come.