if they are actually incestuous (which they aren't) and you ship them (which you do) instead of seeing it as "this is the effects of what they've gone through" then you're the weird one here
fictional characters can't kill, hate, cheat, do morally questionable things anymore without a rando on the internet crying about it. Idk what characters are supposed to do according to u, not everyone wants to die of boredom reading 500 pages of coziness. Fck off to other shores
mind you sam and dean literally had the closest thing to a wedding at the end of season 8 but they want you to believe there’s no incest.
[for a wedding you need a church, which is where they are. you need a witness, which would be crowley. you need vows, which are the promises they make to each other. you need to “tie the knot” and we see dean literally tie a knot around sam’s left hand, which is the hand where the wedding band goes.]
in conclusion: sam and dean are married, which is why later on they use terms like divorce, mistress, etc… to describe their relationship