Boy, am I about to open a can...because I'm going to be honest.
As a Father of a Daughter: I love my Daughter more than anything in this world. I would not want her to be in a mixed marriage (of any race or same-sex either) for identical reasons. Way too complicated. But I would never disown her, and would always be polite to him and his family. I was also a soldier; just because I feel that way about my child does not necessarily mean that I ever carried that over into my military career. Some of the best soldier's I've ever served with were of a different color than I, but civilians don't understand that most soldiers work hard to only see army green. Just because he doesn't want his daughter in a mixed marriage doesn't necessarily automatically convict him of prejudice in his job. In this case maybe so, but don't automatically assume that's the norm.
Now, do I think that's over the top? You betcha. Disowning my child would be impossible for me. So I'd have to accept and tolerate it. Doesn't mean I'd embrace it.
For those of you who want to immediately jump on this to label me, go ahead. When it comes to my Daughter, my loyalty lies in her well being more than any one else's opinion. And don't think that's one-sided, because there are plenty of examples of people of other races who feel the same way.
Having said that, my heart goes out to that girl. I have a nephew whose wife was disowned by her parents. He's a good man, they just didn't approve. It really hurt her, but she is building her life with her new family, and someday those parents will regret what they've done.