Betty and Veronica

Ok, so this is actually a serious question, because I honestly have never really understood this duo, but how and why are they exactly friends? They have nothing in common. They don't have the advantage of growing up together the way that the Betty, Archie, and Jughead have with each other. And I know the parents on this show are suspect, but I've never seen either girl truly interact with the other's parents. For example, we've seen Jughead have meaningful interactions with Fred; Archie have good interactions with both FP and Gladys; Betty have nice interactions with FP and Fred. But Betty and Veronica just kind of randomly interact with each other and during Core 4 stuff where I don't feel their friendship chemistry the way I do with Betty and the 2 boys. EDIT: Obviously, I mean more pre-Season 3 in terms of the parents.