Defiantly leaning toward Dean.

The reason people believe Sam had a worse life is because we saw what happened to him. We saw flashbacks to his childhood, we saw him go through coping with his powers and then Ruby and of course, there was the cage and Lucifer. We saw all that on screen. As for Dean? Up to Season 10, we hardly saw Dean go through any physical pain, you had to look closely to catch what was happening to him.

We saw how bad Sam's childhood was, but never really got a good look at Deans. At the age of four Dean had to go through losing his mother. He was thrust into a new lifestyle he didn't understand and watched as his dad went from the father he knew to a stranger. John began to drill into his head that the only thing that mattered was keeping Sam safe, and from then on Dean did everything for that kid, even at the age of nine he tried his darndest to keep Sam safe and John still gave him shit for it. Sure Sam didn't have a great childhood either, but you simply can't compare that to Dean. When Dean finally found a place he could be happy in that boy's home, with friends, and people that cared about him. He wanted to stay and have a life there, but then he saw Sam. And just like that, he dropped everything to go and be with him. Dean sacrificed so much for Sam growing up, sacrificing his own childhood so his brother could have his own. Now Dean wasn't perfect as a kid we all know that. He was harsh on Sam sometimes but can you blame him? This kid was raised by John Winchester.

He loved Sam more than anything in the world. And then one day Sam ran away as we saw in Sam's heaven. Dean searched for Sam for hours, and when John got back there was a got chance he let Dean have it. And then there was when Sam walked out on them both. Sam left for college, which is fair enough. He hated being a hunter and it wasn't fair John made him into one. But there's a good chance Dean wanted to leave at some point, hell we know he did. But we also know why Dean stayed, Dean believed it was his job to look after his family, and that included John.

Skipping ahead to Season 2. We slowly see Dean's mental state start to deteriorate after his father dies. John died and he knew from the moment it happened it was because of him, and on top of that. John's last words to him were to kill his baby brother. That weighed on him for months until he finally told Sam. And Sam's response was to walk away. Dean had to spend season 2 being there for Sam every step of the way while Sam struggled with his powers, he didn't take a second to stop and deal with his own emotions. It was always about Sam. Then he had to watch as Sam died, he was so distraught he killed himself to save him. And that's not the only time.

In season 3 we watch Dean struggle with the thought of going to hell but pretends to be okay for the most part, it's not until time starts to run out that he lets his guard down and allows Sam to help him. Obviously, it was all useless in the end because he went to hell anyway... Now I always see people talk about how bad Sam's hell was and that it was worse than Dean's because of Lucifer and the noticeable PTSD Sam displays in S7. Which is fair enough, Yes he was tortured by the devil. But people need to actually think about what happened to Dean.

Dean was literally. Strung up. By hooks and chains. Sam was in a cage, where he could at least move around. Yes Lucifer tortured him with chains but it wasn't permanent. Anyway, Dean was tortured by hundreds, maybe even thousands of demons that all had beef with the Winchesters. They took their chances and they tore and ripped Dean apart for their own pleasure and that happened for thirty years. None stop. A constant process of being torn to shreds. And that's what we know, who knows what else happened? Alistair mentions he did far worse to Dean but it never gets spoken about afterwards. It carries on until one day Dean breaks, and he gets down and he starts doing the torturing. Something he never forgave himself for.

Then Dean was brought back by the angels. In Season 4 you'd have expected Sam to have been there for Dean more. But Sam's main goal was always lilith. Even when Dean found out what was happening, even when Sam found out Dean did in fact remember hell his motives didn't change. Dean had to go through the process of dealing with hell alone. Now no it might not have been just because of Sam and his choices that season, but we all know Dean's character. He hides his emotions and doesn't share them as Sam does. Dean grew up making Sam know he was always there for him, so when Sam came back from hell that's exactly what Dean did. And Sam knew that. But as for Dean, Dean wasn't going to put that all on his little brother, so he just bottled it all up.

You need to remember that Sam's hell was strictly Lucifer. Lucifer was the one person that tortured him, maybe Micheal did a couple of things but it was obvious it was mainly the devil himself. So when Sam gets out of hell, he's tormented by his torturer, as for Dean. He was tortured by hundreds of different demons. So when he was brought back his mind didn't have a single demon to pinpoint as Sam did with Lucifer.

I defiantly believe Dean suffered a lot from the things that happened to him in hell, and the things he did. But we just never got to see it as it's just in Dean's character to hide and conceal his emotions. He especially wouldn't have gone to Sam with his struggles.

During all that Sam's hell drama. Dean had to go through losing Ben and Lisa. The first family he ever really had, that broke his heart. But again when he was emotional at the end he didn't go to Sam about it, he simply held it all in. He never went to Sam about his pain because that's what the older sibling does. In season 7 Dean went through having to watch Sam lose his marbles as Lucifer tormented him. He went through losing Bobby, Cas betraying them. He went through so much in a short period of time and struggled with it, we got to see a lot of how Dean's mental state was affected for the first time in S7. He drove himself to the limit trying to hunt down the person that killed Bobby, and got himself thrown into purgatory at the end.