Bloodline defined itself early on with John’s (Kyle Chandler) whispered self-indictment, “We’re not bad people, but we did a bad thing.” From then on, the writers made sure to point out that it was yet another Rayburn lie. The truth of the series is in the confrontation of truth itself and the acknowledgment of sins. The series finale is the culmination of the concept of confronting the truth and its consequences, while also asking again if these were good people who did a bad thing.
The Rayburn family is cursed, and it’s a curse that developed through their own decisions. The final decision is one we’ll never know for sure. John killed his brother Danny (Ben Mendelsohn). At the end of the dock, Nolan (Owen Teague), Danny’s teenage son, stands and waits to meet with John. John is conflicted about telling Nolan the truth. When they do meet, we’re cut off Sopranos style before John can say anything. We can’t explain this situation without first exploring what happened in the previous episode.
John may or may not have attempted suicide. It’s another question we won’t have a direct answer to (as it should be, honestly). Before he regained consciousness, John hallucinated a different reality. Finally, he was confronted by his brother (who is wearing an unconvincing wig). Again, if this is meant to be considered just an illusion or a kind of “crossing over” moment is unclear. The two brothers have one of the few honest conversations in the series, where Danny reveals that all he ever wanted from the family - from John specifically - was an apology.
Of the family, John was the “good” one; the one everyone respected and went to for help. As a teenager, John lied for their father Robert (Sam Shepard), who beat Danny and broke his arm following the accidental drowning of their sister Sarah. The implication is obvious - all of the resentment that Danny had toward John stemmed from the lie; had John apologized at some point over the proceeding thirty years it very well may have kept things from escalating the way it did. He did, technically, during season 1, but Danny didn't truly accept it because John was only giving it while under pressure. It was latent guilt rather than something completely earnest. John’s actions to help Danny over the years were apologies in themselves, but never an actual admission of wrongdoing. So, instead, Danny’s anger and resentment festered.
John is also confronted by his mother Sally’s (Sissy Spacek) truth: that when she thought of the name Rayburn - when she thought of the family legacy - she thought of the inn, not her children. She resented them - her sons specifically - for the trouble they caused her. “You don’t know what family is,” John says. “You never did.” In spitting that reply to his mother, John also considers family. He remembers a conversation he had with Danny when they were teenagers. Danny gave him advice and sharing a brotherly moment. In the recollection, he’s reminded by a vision of older Danny that he wasn’t always a bad kid. Here, John is confronted by truth and consequence. By killing his brother, John also killed the good person that used to be in there. He killed the relationship they used to have and whatever positive memories he had of him. The realization is that he’s been burdened by the death and the only way to unburden himself is, to tell the truth.