Well said - been here just over two years now and it's very definitely home now, but just had my mum out and saying goodbye to her (again) last Friday was utterly horrid. You just get settled and then something happens to remind you of the distance you are away from family. You can't really make sense of it. We also have our first wedding in the family coming up that we are probably going to miss. Like you say, the expat's curse.
Yup - home is magnetic and being an expat is like balancing on a tripwire.