QR, and now many other airlines, has fares that do not include free seat selection (P&R bucket).
ALl the complaining and yelling will not change that fact. They are not blocking 2 or 3 seats just because you are a couple or family. All seats are available for selection by those with higher fares or who pay for the seats.
You chose a (relatively) cheap Business fare and that has some minor inconveniences.
Anyway, most QR seats are solo seats. But if you want to be certain that you sit close to each other, just pay for selection as per your fare rules.