Tell me about it! My wife is a Catholic from Kilkenny, I'm a Presbyterian from Ulster - she has family members who fought for both the original IRA and the British Army (including two brothers who were great uncles, one in each at the the same time), and I have two great great grandfathers who were grand masters in the Orange Order, one in Belfast, the other in Coleraine, and a great grandfather in charge of a Royal Black Institution in Glasgow.
So in our house I shout "no surrender" at my wife, she throws holy water over me, then we sit down, have a cup of tea, and talk about what actually matters in the world...!

lol
I think the real point is you can't live your lives because of what your ancestors did - to be blunt, they're dead, and the world has moved on! There's a great line in a Scottish Gaelic song from a band called Runrig entitled "Ard":
Tha an lasair nad anam aig meadhan do bhith
nas làidir 's nas motha na riaghaltas no ŕgh...
The spark in your soul at the centre of your being
Is larger and stronger than any government or king...
That's going on my headstone!

Chris