On Sam & Dean’s ‘unhealthy’ co-dependence
I think it’s easy to see that their willingness to sacrifice themselves for one another would be unhealthy in any normal relationship, but they don’t live normal lives.
Let’s look at the first example of it: Dean selling his soul to bring Sam back. It’s important to remember that John had done the same thing for Dean, and I never hear anyone say that was ‘unhealthy.’ Why? Probably because it is acceptable, even laudable, when a parent sacrifice’s themself for a child. Seen in that light, Dean’s behavior isn’t surprising. He’s been a kind of surrogate parent to Sam his whole life. While it may be unusual for a sibling to do so, (based on personal experience) I would argue it isn’t unbelievable.
And let’s look at what would have happened if Dean hadn’t. What would Dean have been like if he hadn’t been willing to sell his soul and go to Hell in exchange for Sam’s life? At one point in the series, Dean says to Sam that they keep each other human, and that is all too true. If Sam had stayed dead and Dean had gone on alone, he would have become another Gordon Walker. He would have become a heartless revenge machine just like Gordon. Sam taught Dean to see gray areas remember. Without him, Dean would be a very different person.
Their willingness to sacrifice everything for one another is what keeps them alive and keeps them human. If not for Dean, Sam would never have found the strength to take control of his body from Lucifer, jump into the pit, and save the world. They are stronger and better people because of their selfless devotion to one another.
Lisa calls their relationship unhealthy and tangled because she doesn’t see the big picture as we should. She doesn’t understand that they give each other the strength to continue to fight despite the odds against them. They are, as Dean said, each other’s Achilles heel, but they are each other strength as well.