I don't think "home" is where your family is, I think it is bigger than that, in ways we may not recognize when we are younger. I'm old enough that my original nuclear family is mostly no longer on earth; my children are grown and have homes of their own (and I have grandchildren). I've been widowed twice now, so I live alone. If home was only where my family was, I'd feel homeless -- and I definitely don't
Home is where you feel you belong -- where you have chosen to be, for reasons you have embraced, even if it is not your first choice or fantasy setting; where you have chosen to invest yourself, put down roots in some way, where you have made friends, connections to a larger community, where you feel safe, but also fulfilled.
I think choice is important. People move all of the time, but there's a huge difference in "home" between moving somewhere in your own country because you took a new job, got married, etc.... or moving to a new country you "chose" to go to because there were no opportunities for you in your native land, but over time you put down roots... or worse, moving to a new country because you had to flee to for your own safety. This novel makes that clear for me. Even with family members nearby, nobody in this novel felt "at home" after they were forced to leave their homeland, even though they were all successful at adapting to new locations. Simply having shared memories of a place, or social connections, didn't make it home under those circumstances.