The 1907 St. John genealogy identifies her maiden name as Scribner[1]
And includes a marriage year of 1749 to John St John. I don't trust that work and would like to find a better source. my initial efforts have failed. Thought I'd ask for additional eyes to give it a try. Thanks.
John St. John married Abigail Scribner Aug. 14, 1749 in Wilton, Ct.
John St. John married widow Sarah Scribner Noov. 11, 1749 in Wilton, Ct.
See: https://www.google.com/books/edition/Early_Connecticut_Marriages_as_Found_on/ZCtkUmz95dAC?hl=en&gbpv=1&bsq=scribner