Look, nobody's saying you've gotta dump your old friends (though that would solve the whole FOMO thing one and done). But the whole fear of missing out thing is based on not being there. So be there. Don't go home, but create your own adventure that other people want to be a part of.
You're going to meet hundreds of people abroad from every walk of life, and as you keep traveling, you'll collect them like one of those obnoxious Disney numbers where people drop what they're doing to dance around the main character as if they're not even being paid to sweep that sidewalk or deliver that milk (what's up with that?).