Sam Turning Dark And Evil

Here's some of my thoughts about Sam turning dark and evil. I almost wished that Kripke and Co would've turned Sam evil for real, instead of trying to make it look like it. I would've loved to see Sam really hurting Dean, not just lying to him and sneaking around. Did Dean even care about that or was he pissed that Sam didn't confide in him and tell him everything?
I would've loved seeing Sam be like Angeleus was in Buffy. He wanted to make Buffy hurt and suffer and he hurt all her friends to hurt her more. That was the best acting David Boreanaz has ever done in his career. I just love watching those episodes from season 2 of Buffy. David could never really pull that off on his own show, Angel. He could never really be as evil as he was in those episodes of season 2.
I would think that Sam was turning dark or evil, if he started to not care about the people he's killed or had to kill. If Sam killed someone for the pure pleasure of the kill or killed someone and just shrugged it off, I would think of Sam as evil. Lying doesn't make anyone evil because everyone lies and anyone who says they don't is the biggest liar of all. Sam lying to Dean didn't real hurt anyone, but Dean. Or did it. I really don't know.
It's funny that Dean kept telling Sam that he was going down a dark road, but Castiel told Dean that Sam was heading down a dangerous road. Dangerous is totally different than dark. Dangerous for who? Sam or the world and why did Dean just jump to the conclusion that what Sam was doing was evil.
People keep going on and on about Sam killing the woman in "The Rapture" and "Lucifer Rising". The angels were manipulating everything, so why does everyone blame Sam. Who knows if that nurse is even dead? If she did die, who helped to kill her? Ruby and Castiel( who let Sam out of that panic room). If Sam had never been released by Castiel, than the nurse if she's dead, might not have died and the apocalypse wouldn't have started.
If Sam had wanted the apocalypse, I would've said he was dark and evil. Sam thought he was trying to stop it, not start it.
So it would have been nice to see Sam evil, but I sure didn't see him doing anything evil in season 4, but who knows what he'll do in season 5. If Kripke and Co do have Sam turn evil, than at least make him totally evil, not just try to make us think he's going evil. Have him kill, torture and make people suffer and not care about it. Let him fall in with Lucifer and the other demons and start wrecking havoc upon the Earth. Don't make him half-ass evil, make him bad-ass evil.