Would you disown a child who intermarried?

OOSJ 'admits' that if a child of his intermarried, he would not disown them, and asks:

What does that mean about our commitment to Judaism? What does that mean about our relationship with our children? Does this statement send a wrong message to our children? Does it, so to speak, take the pressure off of them? Should we condemn Mirty's parent's actions … or our own views?

My husband and I have discussed this and agree that (although the children in question are, at the moment, wholly theoretical...) we too would not disown a child who intermarried, although we would clearly be devestated by their action. The comments at OOSJ are fairly straightforward and everyone seems to agree that in the modern world, disowning a child would simply do more harm than good. I would also add that maintaining ties with a child in no way signals that you approve or endorse their choice -- and our children are (I would assume...) intelligent enough to know this. I would also assume that even if you are not cutting ties with your child, your relationship will still, at certain points at least, be strained.
Maintaining ties also does not 'mean' anything for our relationship with Judaism; we're simply choosing a different strategy to previous generations who thought that disowning a child (often for social rather than religious reasons) was the best way to dissuade them from marrying out.
And now, a question: does anyone actually know anyone in today's day and age who's sat Shiva for, or completely, irretrievably cut off contact with a child who's intermarried? Not heard of, but actually known? Or is it a big urban myth?