I've just been going through the ToG thread for this Elizabeth's husband, Isaac Sage. In the other thread several additional children were found for Isaac and Elizabeth including one called Joanna Sage:
Joanna was b abt 1802 in High Littleton Somerset and married:
1) Isaiah Griffiths in 1820 (and if this isn't the marriage, she certainly married someone called Griffith(S)
2) William Roberts in 1840 at St. Michaels, Bristol (entry from FreeREG, father Isaac Sage)
I've just been looking for this Elizabeth again and have come across
this 1841 census record for Cameley in Somerset:
Elizabeth Sage 70 Yes
William Sage 70 Yes
Catherine Griffiths 15 No
I'm thinking if Catherine is the daughter of Joanna then this Elizabeth is very likely to be the widow of Isaac Sage! Goodness knows who William is? I've not looked any further yet!