Promising that he'd help out with the training out here at Bobby's place as often as he could conflicted with Sam's schedule a whole lot. Not to the extreme where he literally couldn't do anything else, seeing as Sam sometimes skipped a couple days out of the training to head back and forth wherever he needed to go, but to the point where he couldn't focus on the one thing that was most important to him right now: finding and killing Lilith. Yes, yes - he knew that there were risks now that the big secret was out in the open about how she was literally the final seal. But if he went about it the right way and attacked her before those other seals were broken, he'd still be able to get what he had been craving ever since that bitch had sent his brother to Hell. Revenge. The satisfaction of knowing that he finally had the power to make Lilith suffer for all that she had done to Dean and himself. Nothing in the world appealed to him more than being able to take in the look of shock and horror on her face right before she faced the inevitable death that was coming her way...God, he wanted it. He wanted it so badly that Sam couldn't even be bothered with focusing on anything else half the time anymore. Even when he was helping Bobby and Dean train everyone here at the salvage yard, Sam was distracted. He was visibly showing people how to properly hold guns, use rock salt, and chant exorcisms, sure, but he was somewhere else entirely in his head. Somewhere dark and dangerous, yet beautiful - to him - all the same. After all, there was no place better than being to stand over Lilith's cold, dead body.
That revenge was a difficult thing to follow through on, however, seeing as he had no idea where he was supposed to even begin. There were no hot leads on where she was, no trails to follow up on - there was nothing there for Sam to look into and he found that to be the most frustrating thing of them all. He was ready for her; Sam was ready to rip Lilith apart, he was ready to fuel that anger that had been licking at his insides for months now into something useful. But seeing as he had nowhere and nothing to go on, Sam had to focus on actually finding her first. He did this routine often. Sam would stay up well past midnight, digging through maps and weather readings; he would be searching for all the omens and potential spikes in the news for something that sounded like Lilith. That was what he had spent all evening doing, in fact. He had holed himself up in one of the empty rooms at Bobby's place, cluttering the area with books and papers and research of all sorts. Still, he came out of it all with nothing. So much to the point that, even though he knew that he was due to turn in for the night, Sam decided to swap out the bed rest for a few shots of something strong so that he could keep on with the inevitably useless path of never-ending research that he was currently treading upon.
Unfortunately, grabbing something to drink required Sam to head out into the kitchen to acquire said drink. That alone didn't turn out to be terribly problematic until, once he stepped into the kitchen, he realized that he wasn't the only one up at this hour. Sam spotted Buffy lurking over by the counter with a glass of water in her hands. He looked down, cleared his throat lightly, then folded his arms across his chest and leaned against the frame of the kitchen door. "Shouldn't you be sleeping?" Ha, like he was one to talk. Though he could get away with lying about what he had been up to - Sam was wearing his black sweatpants and a blue t-shirt. He could have gotten out of bed just now for all Buffy knew.