Simply replace the unfilled areas such as "" and "[date]" with your information.
Dear [name of love interest]
As you know, I am not much with words. When it comes to times of great importance, I tend to muddle the message and never convey the full impact of my feelings.
That is why I am using the written word to convey this message: Because it is one of the most important messages I could want to convey.
That message is this: I love you. I have loved you for a while now, and with each day, my love seems to grow and solidify. It has reached the point that I feel my love for you physically, pounding in my heart and almost crystallizing in the air between us.
I hope that you feel this love as well, and that the message of this letter is pleasing to you.