Fantasy series early 2000's? Partners control elements, Male character chooses female in a ceremony

The FMC was chosen by the MMC in a ceremony after FMC completed schooling, they had to work together to control earthquakes (maybe other pairs controlled other elements?). FMC didn't want the MMC to choose her, he wasn't thought to be a strong/serious partner. They end up in love by the end of the series. Possibly had "Hero" in one or more title or the series title. Published probably sometime between 2000--2010, 5 or 6 books in the series