They’re so not all right, and Bobby knew this as he left them by that bridge that they can not cross over. Don’t be hard on Bobby. He’s neither their father nor a couples therapist. He’s their friend, and though more a mentor than a peer within the hunting community, he knows you won’t get far trying to boss around a Winchester. And Bobby wasn’t there to hear what Sam said. He doesn’t know the half of it, because Bobby also doesn’t know Sam Winchester has demon blood and wields the Hand of Ipecac.
Sam has been so silent this season everyone figured Kripke had it out for him, but I held fast to the belief his silence spoke volumes. And now we know. Now we know more than we wanted to know about just what Sam is thinking.
I don’t care if Sam tries to use the excuse he was under a spell when he told Dean those hurtful things, because that’s BS. Those words were spoken from his subconscious and they were real.
The siren planted a hyacinth at the scene. In the language of flowers, the hyacinth is the symbol of sincerity.
Sam was the most honest in this episode since early season two. Still, it seems honesty is not the best policy and all those times Sam has had no response to Dean it is understandable. Better to say nothing than to say the wrong thing. But when Sam lets it all out: watch out. I think of what he said in two parts. First off there is the whole, I’m better-stronger-smarter than you comment. To me, that was a testosterone filled sibling rivalry comment. Sam has always been competitive and strives to be his best at whatever he does. It would be natural for him to think he was superior to Dean. In HS I’m sure he felt his academics gave him an edge, later once he considered himself a hunter he naturally wanted to be top of the game there too.
It’s the second comment that was more barbed: “You’re holding me back.” It’s like saying he doesn’t need Dean at all. And that’s one of Dean’s deepest fears, the fear that causes him to project an entirely different Sammy onto the man Sam is now. In “Metamorphosis” Dean spoke his fear: “You don’t need me. You and Ruby go fight demons.”
Sadly, that’s exactly what they were doing and doing well until Dean showed up. Again, in Sex and Violence, Sam reminds Dean he doesn’t need him. He and Ruby will find Lillith. Dean isn’t strong enough for the fight. Part of this could be Sam’s new found protective instinct over Dean. It’s an instinct of a big brother who considers the other lesser or weaker and in need of protection. Sam has demonstrated this all season and Dean has fed that need from nearly being eaten by the Rugaru in Meta, to his capture in MM, to his nightmares, the drinking, his paranoid collapse in YF, his beating at Alastair’s hand. Sam has been there to save his ass.
But the whole: “So you tortured souls, boo-hoo!” Holy crap Sam, what a bastard!
Which makes me think of the Foreigner song: “Cold as Ice”
That would be Sam. Cold as Ice. And much of it is protective instinct. He wants to not be hurt, not be rejected.
So even if the siren’s venom made Sam think the thoughts he did, what planted them? Do his “power-up” sessions with Ruby stir the demon blood and make him more mean, more cruel or spiteful? More like a demon? Beware when you fight the monsters, lest you become one of them.
Is that why Dean was so eager to point out to Sam that he slept with monsters…meaning you are one: I’d hunt you. Remember that was sincerity without the venom.
Season One "HellHouse" Sam getting pranked on. 
