User blog:Sachoras/Cersei - friend or foe?

Despite her usual cold demeanor, Cersei was actually quite sweet and compassionate towards Sansa in A Man Without Honor during their discussion about Joffrey. However, in Blackwater Cersei does a complete 180 and reverts to her old ways of ridiculing Sansa and picking on her for sport. Does Cersei hate Sansa or was she just drunk?