Hello,
I have come across Alberta in some Diamond family history resources. I have found her listed in some resources as Bertha (or Berta). Her parents were Barnabus Diamond (b. 1822) and Elizabeth A. Henderson (b. 1826). Alberta was one of five children. There is more information on the Diamond family at the United Empire Loyalist Heritage Centre in Adolphustown, Ontario (uel.ca) where they have a research library. The librarian would be happy to do a more indepth look-up for you. Send requests to research.uelc@gmail.com

Regards
C.M.