Hi guys and thanks for trying to help me out!
Well, theoretically you are right, everyone is not mean to live just in one place.
Admittedly, friends, social activities, sports and language courses help a lot.
Let's put it this way, probably some of us are less meant to move than other. As much as they like travelling and seeing new places, they could never find another place for them to live other than their own country or city. I don't have scientific evidence

but I'm sure for some of us this is the case.
Don't get me wrong, there's nothing wrong with it but it does affect an international relationship in the long term.
Luckily, I like moving myself or at least remain in new places for much longer. So, a combination of my attitude and my wife's effort to 'resist' longer in my country will do just fine!
Happy Valentine's Day!