Unusual 18th C. Needleworked American Painting

This very early painting is circa late 1700s or early 1800s. The piece seems to be from the Boston area, and it has needlework accents. It depicts a woman in the country with her dog. On the reverse side is the original back paper with what seems to be a letter or story related to the painting. From what can be read of the script, it mentions her "faithful and loving dog" and the admonition "thou shalt not leave me, Sylvia". It says "...she had "travelled without money over all Lombardy, the roads of Savoy.." and after this the writing becomes illegible. At the bottom right corner it says "Painting and Needlework", then more illegible writing and "Boston". There is a partial paper label from the original framer reading "Stokes, Carvers, Gilders, Glass and Pictures. Milk Street. Framed and Glazed in the...Likewise, Gilded, Burnished Gold and Glazed..." and then a bit more script. A mystery waiting to be solved, this piece measures 15.5" tall x 13.5" across.
Condition Report: Painting is in excellent condition. The original back paper is fragmented as per the documentation.