Listening to Dean say it, with John's own memories backing it, was one of the most painful things he'd ever endure, hearing his son's pain and knowing there wasn't a damned thing he could do for him but talk. There were no easy fixes and John himself wasn't in any place to fix anyone when he was still so broken inside, something he fiercely tried to hide all the time. But he had to do everything in his power to try.
After a long, long moment, he nodded at Dean, a painful but necessary admission. He'd survived a war, he'd survived losing his wife, he'd survived Hell to crawl out of it, he'd come back from the dead – and now he had to say that all of that didn't mean that he could face this without thoughts like that, without the deep, poisonousness need to just make it stop.
"More than I want to admit to myself, let alone anyone, like your mom. Been nights I've woken up and felt like a drowning man, that no matter how hard I struggled to shake it off, it'd just drag me down and kill me."
He took a swig from the bottle and spoke again, this time his voice low, ragged, and the words themselves slow, as though it was talking an incredible effort to get them said. It was because it was. John didn't want to be the weak man in his son's eyes, not after all the other ways he'd failed them over the years, which was why that demon picking out Sam's thoughts that he wasn't sane anymore had hurt. But Dean needed this more than John needed his dignity, so if helping his son meant sacrificing what was left of his perceived strength in his sons' eyes, he'd do it. For both of them
"There've been times I just hoped it would, just so it would stop, so I wouldn't have to remember, so I wouldn't have to admit the inside of me is the huge hole." He took another drink to cover the way the words 'huge hole' caught in his throat, his hand surprisingly steady, but it was an effort. His words made him weak, he was certain, but he wouldn't let his actions make him that too. "I couldn't even tell Mary about that feeling for a long time because I thought she'd think I didn't want to be here, but I did. I do. But it didn't make any sense to me, to want to be here, but want it all to stop, how was it supposed to make any sense to her?"
And this wasn't even all of it. It was just one small aspect, and there would be so much more with more of Dean's questions. Clearly his throat to try and dislodge the tightness that kept growing, John continued. "In the end, as much as I was holding her at arms length, then half-arms length, I was still holding on, so goddamned tight. So I started to tell her. Just like I'm talking to you, because I know what I need to hold on to, even when I'm holding it away. Your mom, you and Sammy, you three most of all."