You certainly seem to have started well with your research into your paternal great-grandmother!
As you have also found, there are many variations in spellings of surnames and that it was always popular to name your children after their parents and other family members to continue the family line of names used. This does indeed lead to a few confusing moments when trying to trace farther back in time.
Before 1864 records were kept in the form of church and parish records; while some of these have regrettably been lost over the years, all the surviving records have been sorted into county-based genealogical centers
. For Country Antrim, this would be Ancestry Ireland through the Ulster Historical Foundation
In 1864 civil registration was introduced in Ireland, which is when we started seeing the formal registration of births, marriages, adoptions, and deaths. These records have been kept at the General Register Office
of Ireland (GRO), to this day.
We have several posts on the forum that may be of interest, including Tracing your Irish ancestors:
A three-step guide by Brian Mitchell.
I'm sure our Industry partners and fellow members will have some advice also. We hope this helps with some additional resource information.