People you meet later in life - even much later, even when you have a wife and kids - can absolutely come to know “the real you.” (I might describe “closeness of relationships over time” as “asymptotic, with an upper limit” or at least “with diminishing returns,” if we want to get really math-y about something that is not really measurable.)

But you have to be open to that, and it also requires a lot of social skills that are not really otherwise demanded (in fact, arguably discouraged) among, particularly, men in developer/software engineering roles.

That’s not to say that you shouldn’t maintain relationships with school friends. But, especially if none of them are nearby, you owe it to yourself and your family to build a local community for yourself that’s on that same magnitude of closeness. It’s a process that takes 5-7 years (again, just making up numbers here - this depends on your personality, how far along you are learning social skills, and who’s in your community), but the best time to start is always now.