Hi Marit!
I'd love to know if you've already picked your destination.
As a fellow female solo traveler who has solo-travelled Ireland before settling down on the West Coast, I just wanted to put my recommendations out there for you.
I'd personally staying in a smaller town, as it will be very easy for you to make friends and get help from locals.
Have you considered a place like Achill Island, or the lesser-known Clare Island off the coast of Mayo for a truly immersive and authentic experience?
Besides, I can also highly recommend Dingle for Christmas and New Years Eve. Dingle is very popular for Christmas because the town celebrates
Wren's Day (or St Stephen's Day), and has a big NYE's celebration with fireworks. There's also lots of traditional B&B's to choose from.
Happy holidays,
Alinde