Pretty much everything has been said and I agree with.

I think the pairing that got even close to a romantic pairing is Vaan and Penelo. And even then, in XII, it was clearly more like a childhood friendship going off exploring rather than a romantic thing. It's only in XII:RW that there's real hints of romance, and even then it's down to interpretation.

I quite like how XII handled relationships actually. It was very mature.