You probably have all of this.
Is this her marriage?
1883, Reg at COBAR, #4057
William MAY Eliza HAMPTON
The children I see listed on NSW BMDs with parents William MAY and Eliza are:
1884, reg at Nymagee, #18957
Eliza H MAY1889, no place of registration noted
Joseph H MAY, reg no: V188901369 160
I note that her birth registration is for Eliza J HAMPTON
There is another child with parents William and Eliza J but registered at Sunny Corner. Given that William Henry and Eliza HAMPTON's deaths are registered at Sunny Corner it would seem feasible.
1888 reg at Sunny Corner, #15994
Alice M M MAY, parents WILLIAM and ELIZA J
Austcemindex has a photo of the grave of William and Eliza HAMPTON at Meadow Flat General cemetery. (There is no mention of either Eliza or William MAY that I could see.)
http://austcemindex.com/inscription.php?id=2755650None of this helps find Eliza's death but does appear to show that she had connections in a wider area.
Judith