... Think like a sociologist. Observe. Make a note of it. Report on findings.
You can walk toward an Irish woman who is standing in place and you can maintain a resolute "I'm going to pass by where there is currently no space to walk" demeanor, and she will probably not see you.
You can look directly at the side of her eyeball, where you can see the black of her pupil and you can watch the steady, unaware solidity of it. She does not know you're there, or that you're going to try to pass where she is.
It's easy to see the tiniest flicker of an eyeball in a person who is aware of another person's physical presence. There is none of that in the eye of the Irish woman. She will stand there exactly right smack in the way of your only pathway beyond where her body stands.
It's an amazing thing to see, once you notice it. It's exasperating and baffling, sometimes, unless you can learn to temper that impulse, and accept it in some way.
My way is to think of it as a cultural phenomenon, an Irish folk-way. There's nothing obstinate or malicious about it.