In Season Two, she was exposed to this behavior even in the people she admires most. I'm glad that we didn't go the route of woman-versus-woman implied in Diane Lockhart's earliest characterization, because that's something we've seen before. But to see Will engaged in political and legal ugliness, while simultaneously coming to a complex and layered understanding with Eli Gold and with Kalinda, means that in the end of the season, when Diane almost regretfully has to inform Alicia that her career is on the upswing -- as long as she's willing to use her connections -- she's got the perfect recipe for a whole new understanding of the world. The catalyst, of course, being the ultimate reveal: That even her greatest friend is not above personal betrayals.
But we've already seen Alicia freak out, several times in fact, upon learning that not everybody loves being Good as much as she does, and that they regularly benefit from doing the things she won't do. Simply putting her on that wall and tipping her over it wouldn't work nearly as well as presenting her with a number of open options -- Will, a political career of her own, a corner office -- and watching her negotiate these with her eyes open. That it's possible to swim with sharks without becoming one is obvious, but it involves a constant rigor that -- on her best day -- wouldn't trouble Alicia at all. It's just that the world keeps throwing shit at her and taking those good days away.
The showrunners -- a justifiably lauded pair of married writers named Robert and Michelle King -- have described the show's first iconic moment (backstage, immediately after standing by her man in a press conference, she slaps the shit out of him) as being, in a way, about slapping herself awake.
Alicia Cavanaugh was a rising star in the legal world fifteen years ago, before she left it all behind to marry the promising politico Peter Florrick. She didn't want to try to "have it all," so she moved out to the suburbs and raised her two gifted children; she put aside thoughts of a brilliant legal career and finally closing the deal with Will Gardner, and she was happy. The fervor with which teenagers Zach and Grace now engage with politics and current events tells you a lot about how they were raised; both Peter and Alicia were -- and still are, I would argue -- True Believers in the Jed Bartlett sense. No matter how dirty Peter's hands get, you can still see the man she loved, and married, and while this is part of the genius of the show it's also necessary: If he were wholly a monster, the show couldn't exist.