The tortured girlfriend role

I recently rewatched Donnie Darko, Dangerous Lives of Altar Boys, Life as a House, and the United States of Leland. Not only is Jena Malone in all those movies, she plays the exact same role. Girlfriend with problems, or girlfriend who is troubled but slightly less than main boy, or girlfriend who reflects problems back on boy to bring him to a pivotal realization. My sister and I used to call her The Tortured Girlfriend. Before that we knew her as The Girl from Stepmom. She eventually started being a more central character instead of adjacent girl, but I'll always remember those heady days of The Tortured Girlfriend.