She won the last race of the 2005/2006 season in Oslo and thus secured third place in the discipline World Cup mass start. In the World Cup she was able to win a total of eight races, three of them in the 2006/07 season. At the 2007 World Championships in Antholz , she first won silver in the pursuit. The highlight and greatest success of her career was the individual world title, which she secured with a faultless shooting. On February 11, 2007, just a few hours after winning the bronze medal with the Norwegian relay, she surprisingly announced her immediate retirement from biathlon; She named training and travel stress as reasons. Although she did not run the last nine races of the season, Grubben still finished 6th in the overall World Cup at the end of the season and was the best Norwegian of the 2006/07 season.
She has been married to the former Norwegian national biathlon coach Roger Grubben since summer 2006 . They have a daughter (born December 2007). Because of her fear of flying, Grubben was unable to take part in several competitions (e.g. at the 2003 Biathlon World Championships in Khanty-Mansiysk , Russia).