Supernatural has spent 14 seasons so far raising the stakes higher and higher, and that has meant the Winchesters giving up more and more, to the point that they've given up their lives more than once. Sure, they were also brought back in true Supernatural style, but that's no longer a guarantee with the final season on the horizon.
Yes, Supernatural will end after Season 15 in the 2019-2020 TV season, and star Jared Padalecki weighed in on what he wants to see for Sam and Dean's ending:
It's our last season. But I want it to feel like it's gonna go on. I don't want Sam to feel like it's the ending. I want Sam to feel like he's still making a difference, that he's still helping other people. And so, I don't want it to feel like doom and gloom, too much...I want Sam to still fight, to keep fighting and keep supporting his brother and his friends and his family.
He'll have played Sam for a decade and a half of his life, on a show that introduced him to his wife, among other things. It would be awfully sad if the series ended with Sam and Dean feeling like their efforts have been for nothing and they couldn't make a difference.
Considering that they're facing off against God/Chuck and a whole lot of creatures that they'd already killed/banished to Hell following the killer Season 14 cliffhanger, it would be hard to blame them if they despaired at least a little bit. Losing Mary and Jack in quick succession surely won't help. Still, they have each other, and they have Castiel. Maybe Jared Padalecki will get his wish and the Winchesters will keep on fighting even after the final credits roll.
Jared Padalecki once floated the idea of a Butch Cassidy and the Sundance Kid-esque ending for Sam and Dean, which wouldn't mean an overwhelmingly happy ending, even if it would be pretty epic. Based on his recent further comments to TV Guide, Jared Padalecki doesn't actually know how Supernatural is going to wind down the Winchesters' stories. Padalecki went on to say this:
If they die--I don't know, I don't think it's written yet--but if they do die, I want them to die going out doing something they love that will make the world a better place. Part of me thinks that's the only way to end Supernatural. Because if the boys were alive, they'd be hunting, and if they're hunting, I want to see them hunting. Maybe that's the way it goes, I don't know.
There are ways Sam and Dean could die without it being 100% heartbreaking. Channeling their inner Butch and Sundance would be one way to go. Honestly, as long as it's on their terms rather than because of murder, I think Supernatural fans might be okay with it. That said, it would be awfully tragic if one of them died and the other had to go on without his brother. They've tried to build solo lives after losing each other before, and it's never ended well.
We'll have to wait and see. The stars explained why Supernatural is ending after all these years, and it's hard to fault them for making the big decision. Besides, the Season 14 finale set up what could be a truly remarkable final season, so there's a lot to look forward to. Supernatural returns for its fifteenth and final season in the fall.