This is just something that popped into my head...

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Tell me why you broke me down and betrayed my trust in you
I'm not giving up, giving in when will this war end?
When will it end?

Sam would never forget the way he'd felt when Dean had walked in on him using his powers that night. The guilt that he'd tried so hard to ignore had crept up inside him and he'd said the first thing that came to mind. But how could he explain the fact that he was killing demons with his mind. It wasn't something that he could just drop into conversation. He hadn't even come to terms with what he was doing himself; how the hell was he supposed to explain it to his brother? How could he explain that the only time he felt good about himself was when he was using his powers and saving people. That's what it was all about; saving people. He hadn't been able to save the people he loved – Jess, Dad…and Dean. He knew that this could never make up for it but it was like some sort of redemption. By saving other people…he'd save himself. He'd change his destiny somehow.

He didn't know if what he was doing was right; he'd seen how the others like him had turned…Ava…Jake; he didn't want to end up like them. But what if he lost control one day? What if him becoming evil was inevitable? This was just a number of the questions that Sam had been asking himself everyday. It was like his life was one big nightmare that he could never wake from. He had no answers; the truth was that he didn't know what the future held? Sam wasn't sure that he wanted to know. Getting through each day had proved to be hard enough.

'If I didn't know you, I'd want to hunt you'

Those words had been echoing inside his mind ever since Dean had said them. Sam didn't care about what other hunters thought; he cared about what his brother thought of him. He didn't want Dean to hate him. This was why he'd lied in the first place; he'd only just gotten Dean back. He didn't want to have to look at Dean and see the fear in his eyes. The fear of knowing that there was something evil inside him. He didn't want his brother to hate him. He'd rather die; Dean was all he had left. Sam wasn't going to lose him again. But he could sense some sort of block between them, caused by lies and everything that had happened.

He hadn't told Dean about the demon blood because he didn't want to scare Dean, he saw the way that Dean looked at him and decided that he didn't want to give Dean another reason to think he was some sort of freak. Sam had been petrified at the thought of there being something evil inside him; eating away at him until it was ready to be unleashed. He'd been so preoccupied with Dean's deal that he hadn't really had a chance to dwell on it. But then suddenly, Dean was gone and he was 'immune' to Lilith's burning bright light. He'd tried to save Dean; he tried everything. But nothing came out of it. He'd been broken and alone and he'd realised that…he could never get rid of the evil inside him but he could use it to get Lilith…if she couldn't kill him then surely that meant that he'd be able to kill her. Or so he thought.

Every time he used them he remembered how Dean had practically begged him not to use them and he felt the guilt wash over him. But each time he'd ignore it and tell himself that he needed to do it. However he knew that Dean was right; he couldn't continue this way. Not without something awful happening. He'd seen the panic in Dean's eyes and he knew that he had to stop. It was his choice; he just didn't know how long he'd be able to resist.