I'm gonna break the rules and name a TV character. An easy target, at that.
Heroes' Nathan Petrelli. He's a kind of good guy who makes bad decisions, then goes bad, then good, then he wants to out everyone then he's a God fearing man and wants to not out everyone, then wants to help everyone, then wants to make an army of superpeople for no reason at all, then want gives up all the superpeople to the government so the government can capture them, but then changes his mind because the government captures them, then he fights the government and becomes Sylar, but he's really still Nathan until he REALLY becomes Sylar and dies.
Also somewhere along the way he got divorced, lost custody of his kids, became an alcoholic and grew a wicked beard but soon after still was able to be elected as a senator.
I gave that show waaaayy too many second chances.