Your are correct that Daniel and Nancy Butler Over are buried in Seaside Cemetery. According to the Cemetery Inscriptions and Burial Site os St. George, Maine they are buried in Row 29, Lots 1 & 2. Names are Asenath Over, d. 1 Sep 1873 age 60. Daniel Over, d 21 May 1865, age 80-8-8 and Nancy, his wife, d. 7 Sep 1868, age 78-3-20. I have looked in other books that I have but cannot find the birth of Nancy in St. George Vital Records. When she was born the Town of St. George was combined with Cushing, Maine and they didn't split until 1803. I did find a William Over that was in the Civil War from St. George, ME. I found some Butlers in St. George but they do not appear to be your Butler Family. The name Butler was not that common in the research that I have done in St. George. I know there was a Butler in Thomaston, as I have read that in Come Spring by Ben Ames Williams. The Butler in Thomaston was selling land around Union. The name Butler is common in Warren, Union, Appleton & Hope. When I lived in Appleton a couple of years ago it was a very common name. I checked all my extensive books from Appleton but did not find your Nancy Butler. Thomaston is close to St. George so you might want to check with the Thomaston Historical Society to see if they might have any additional information. Sorry I couldn't be of more help.
Joanne Clark Borden