You're adding two and two and making five there, @Mooshamoo.
You grow up in a certain community where everyone has the same accent, everyone knows what you're talking about when you chat about the Leaving Cert or some deadly poem you had to kearn by heart for the Junior Cert (and then it never came up) and suddenly you're the mother of kids who are pronouncing their THs like Fs , who are learning songs in school that you don't know, whose playground games come with a different vocabulary - yes, of course it's odd. It doesn't mean you hate it or you're going to suffer an existential crisis over it. That's too much of a leap.
My own children recited the Pledge of Allegiance to the flag of the United States every day in elementary school. I only learned this when my third child was in second grade. I'm not sure what I thought that flag was doing lurking in the corner of all the classrooms I ever visited, but heyho... My DDs were Girl Scouts - sold GS cookies - DS was a Boy Scout. They went through all the rituals of American childhood and youth - graduation from 8th grade, Homecoming dances, taking unfamiliar exams in an unfamiliar format, driving at 16, high school graduation, prom, one of them even pledged a sorority.
It is strange AF to see your children doing stuff you previously only saw on The Brady Bunch or glimpsed in the pages of National Geographic, and meeting women with the kind of hair and clothes and cars and homes I had gawked at on Dallas was mind blowing. I read high school academic catalogs from cover to cover and did hours and hours of research about university application and financing and threw myself into the new normal. I was even the cookie mom for one DD's girl scout troop.
I grew up in a very left leaning Irish home in the era of anti-American protests at Greenham Common, at the height of America's very dirty war in Central America and in the wake of America's golden age of regime changing geopolitical games all over the globe as the Cold War reached its nadir. My classmates and I watched BBC, UTV, ITV, and Channel 4 programmes as well as RTE and enthusiastically followed Ska bands and embraced the anti-Thatcher feeling of the times. If I hadn't met exH I wouldn't be living in the US, and my children would probably be Irish, or possibly British, or who knows, maybe even German. I have relatives all over the place and we all come and go.
My schoolmates - most of us managed to be simultaneously fans of various English Premier League teams as well as diehard Dublin GAA fans and supporter of Irish rugby - are scattered all around the world, and of those in Ireland, a large number formerly lived abroad. I think it would be very odd in this day and age to encounter an Irish person with a deep hatred of Britain.