Everyone messes up in relationships and has peaks and valleys in their personal lives. When I realized it wasn't the end of the world and I would keep on standing, I knew it was going to be OK.

Zajac. Debuting at the Sundance Film Festival the film won the Special Jury Award for Outstanding Ensemble Performance. In 2012 in addition to filming the third season of Shameless Rossum signed onto two film projects.

She currently stars on the Showtime dramedy Shameless as Fiona Gallagher. Her role in Mystic River (2003) garnered her wider recognition.