Being the first in your family to move away is scary for everyone. You’re opening a door they can walk through later.

Leaving first carries a weight that has nothing to do with the distance. Your family loses the assumption that everyone stays, and you lose the reassurance of a route somebody has already walked. Both of those are genuine losses, and neither means the decision was a betrayal.

Keep the contact regular enough that the leaving does not read as disappearing. Tell them the ordinary details, not only the achievements. What you are building is not just your own life but a path that becomes thinkable for whoever comes after you.