I think it's happened, and I'm not sure exactly when. We may have crossed over to accepting our host country as our "home".
I have noticed recently that the complaints are becoming fewer and farther between. I personally find myself listing more of the things that I do like, instead of the things that I don't. I find myself making excuses for the aloofness of a local, and even find myself taking on the traits of my hosts. I say "excuse me" far less than I used to, and have even found it very annoying when people say it to me too often.
I think the kids have crossed over as well. The other day, the oldest expat said to me how much he "missed" his friends in Germany.
Of course this has happened after living in a location for a year and a half...because, that's usually the point when we start to think of our next move!