Bussaglia began her career playing for Olympique Saint-Memmie playing at the club during her youth. She spent two years with the senior team before being selected to attend the CNFE Clairefontaine, the women's section of the Clairefontaine academy. After leaving the academy, she joined D1 Féminine club FCF Juvisy playing 14 matches and scoring two goals in her first season. In her second season with the club, she played in all 22 league matches scoring four goals helping Juvisy win the league title. She had another successful season before joining Montpellier. At Montpellier, Bussaglia became an established international player and helped Montpellier to two top table finishes, including helping the team win the 2008–09 Challenge de France and qualify for the newly created UEFA Women's Champions League in her final season.
In 2009, Bussaglia signed with Paris Saint-Germain and, in the process, joined a club, which included international teammates Camille Abily, Sonia Bompastor, Bérangère Sapowicz, and Laure Boulleau. In her first season with Les Parisiens, despite the club having a respectable season, Bussaglia struggled appearing in 18 matches and scoring only two goals in the league. The midfielder compensated her uneventful performance in the league with a decent showing in the Challenge de France netting the fourth goal in Paris Saint-Germain's 5–0 win over her former club Montpellier in the competition's final match. The victory assured Bussaglia her third career Challenge de France title.
In the 2010–11 season, following the departures of Abily and Bompastor, Bussaglia was handed the reins to the attack and quickly blossomed scoring four goals in Paris Saint-Germain's first five league matches of the season. On 26 February 2011, she scored both club goals in a 2–1 win over Le Mans. Bussaglia ultimately finished the season appearing in all 22 matches and scoring a career-high ten goals. Despite failing to score a goal in the final six matches of the season, Bussaglia was still an important cog of the team as Paris Saint-Germain qualified for the 2011–12 edition of the UEFA Women's Champions League after finishing runner-up to champions Olympique Lyon. For her performances during the season, Bussaglia was named the UNFP Female Player of the Year. She was also named the Best Player of the 2010–11 Division 1 Féminine season by her peers.