Getting a car or public transport?

Hello all,

I've just moved to Ireland, and I'm currently living in Sandyford, Dublin 18.

My girlfriend needs to get to and from work, which is located in Summerhill, north west Dublin.

Do you have any recommendations for how she gets there the easiest? Of course it would be great, not having to buy a car and pay for the crazy insurance. The public transport seems kinda bad out there.

Any advice?