It would be helpful to know when your trip is scheduled for.

ime, additional availability has sometimes opened up in the days immediately before a flight.

[That said, I recall that there was a period last summer when this did not appear to be occurring (to many posters' distress) and then all of a sudden new availability appeared for all flights over the next few weeks --- as though some manager of North American reward seating had been on an extended vacation!]

Depending of course on how far along your relationship with your gf has developed, I agree with others that you should be looking for two seats in either business or first.