The song P.S. I Love You by Billie Holiday is a love letter set to music. The lyrics convey the message of a person writing a letter to their loved one, expressing their thoughts and updating them on their life. The writer shares that the weather is cool, the folks are fine, and they go to bed early each night. They also mention a recent rain and wonder if it was dusty on the train. The letter ends with the writer telling their loved one that everyone is thinking of them and that they love them. The song has a simple, nostalgic tone, evoking the feeling of a bygone era when letter writing was a more common form of communication. Overall, the song is a sweet and sentimental expression of love and affection, written from one person to another. The lyrics are straightforward and heartfelt, making it easy to see why this song has become a classic and enduring love ballad.