I think I am having one now...completely reverse experience than other posters!
In a nutshell, I came here for a temporary assignment, leaving a life I loved and I had built the way I wanted, because I missed being a daily (or almost daily) part of my family's life. I was absolutely sure that I would go back where I came from. I didn't even pick Switzerland for its own sake, it was just "a possibly interesting location" for me, so why not?
Having moved many times to different countries, moving once again was not a shock, but very shortly after I came, I thought that, while coming back to Europe had been a good decision, I had made a mistake in choosing Switzerland. Every day I would wake up and think what I could do to leave this country. I wasn't feeling lonely, I met lots of friends (Swiss and foreigners), I went out a lot, travelled, spent time with my family, learned new things in my profession, progressed a bit with German, had no problems with apartments, neighbors, landlords. From the outside, I looked happy and successful.
Still, nothing of this really gave me satisfaction, I felt like I was mutating into a depressed, weak person that I didn't recognize anymore. I started having health problems derived from my psychological struggle - we can cheat ourselves, but sooner or later our body reacts. I still was trying to do all I could to leave the country.
But guess what? Switzerland was "trying harder" - every single time a concrete opportunity to leave would pop up, something bigger and better would happen: a small, personal success with the language, a salary increase, a promotion, meeting a new friend with whom I have lots of things in common, meeting a special someone, finding a new coffee shop I liked, starting a new activity I enjoyed, etc. So I would say all the time: well, I can't really leave now, can I? I'll wait a little bit longer...
Almost two years later, "I need to leave this country" has turned into "Well, I'll be darned, but perhaps this is where I am meant to be after all, at least for the time being, not too shabby, perhaps I'll stay a little longer..."
I have the feeling that the goodness has just begun and there is lots and lots more to come - hence I think my honeymoon has just started, and I am quite enjoying the ride