Abby was the widow of John Bolster when she married Caleb. I have estimated the year of this marriage.
The RI Cemetery Database has an Abby Jane Remington buried in Cranston Historical Cemetery 2, with dates given as: c1823 - 31 Oct 1906. This must be the same individual. She is probably Abigail Luther, because a witness on the probate for Caleb is Addison Luther.