“Same circumstances”…this isnt about Sam not wanting to save Dean , it’s absurd. It’s all about choices/free will and the way they love equally each other. Dean’s love for Sam is consuming and beautifully selfish , he needs Sam like he needs air , he lives for him and him only.
Sam’s love for Dean is more hidden and selfless , he would put Dean’s choices before him even if it means being miserable or/and killing himself.
They are both the embodiement of two powerful and extreme kinds of love , no middleground for the Winchesters codependancy.
“What’s the difference between love and devotion professor ?"
"Well…you can love many people but devotion is too deep and too strong to be shared. It is when the world is falling apart all around you and people think you’re drowning in the darkness because they don’t see it. His soul shining so bright that you are blind for everything but him. Your soul finds comfort only in his light and your body’s only purpose is to make sure it never fades. It’s almost…religious , extraordinary. You smile when you should be crying."