Because you like John Yossarian in Catch-22
A former high school outcast, Rebecca Doppelmeyer is tentatively shaking off her misanthropic personality. See them in Ghost World.
Kara "Starbuck" Thrace will beat you in cards, drink you under the table, then fly circles around you in her fighter plane. See them in Battlestar Galactica.
Sharply perceptive and stubbornly principled, Jane Eyre might not have a very loud voice, but she knows when and how to use it. See them in Jane Eyre.
This thrill-seeking driver lives by a very particular moral code. He stands by his word and he's loyal to a fault. See them in Drive.
Holly Golightly spends so much time trying to be other people's dream girl, she doesn't really know what kind of girl she actually is. See them in Breakfast at Tiffany's.
Although Theon Greyjoy is treated well, he's still essentially a hostage. And that isn't so easy for him to forgive. See them in Game of Thrones.
Though raised to think of himself as a monster, Quasimodo has a heart that holds nothing but compassion. See them in The Hunchback of Notre Dame.
Veronica Mars is a sarcastic private eye whose biggest mission is surviving high school. See them in Veronica Mars.
Calling Alicia Florrick a "good wife" is damning this smart, capable, thoughtful woman with too-faint praise. See them in The Good Wife.
While his twin tries to save lives, Millions Knives does the best to end them. See them in Trigun.
Big Boss is a disillusioned mercenary commander who wants to create a world for soldiers (and soldiers alone). See them in Metal Gear Series.
Dr. Gordon Freeman is a brilliant physicist is a quiet hero. And given all the violent aliens, he better be. See them in Half-Life.