Spoiler alert, should you be worried about that sort of thing.
Essex County Volume 1: Tales from the Farm
So the nature of reality in Tales from the Farm has me a little bit worried. I mean, on the one hand, it's mildly weird even from the beginning. The opening has Lester flying over his uncle's flat, boring generic-crop field, but then it doesn't come up again until the very end. He does mention his alleged superhero activities, at least to Jimmy: "I'm a superhero. There's an alien invasion coming. Just scouts so far. I gotta kill 'em before they can report back to the main fleet."
And Jimmy just goes with it. But of course you don't see the actual fighting of aliens, so it's easy to assume that it's just a game, like it's easy to guess, what with the relentless realism of the rest of the comic, that the flying at the beginning was just a little boy daydreaming. It's easy to think that they're playing until the end, when aliens do actually show up and Lester flies, and Jimmy dies.
It'd be cake to assume that this was imagination, too, except for the part where Jimmy actually does die. It's not the sort of thing a kid as lonely as Lester is likely to make up, and when he gives up his mask and cape it's certainly very final. In which case he is a superhero, and that, at least to me, makes the whole comic different, because that means maybe Jimmy was a superhero too.
His mother may have been a super-sort, but Jimmy seems like the more likely candidate for heroic parentage. That would explain why he's so calm about being killed by aliens. It also brings up the question of whether his head injury forced him out of a heroing career and not just the NHL. It would certainly explain some of his intense bitterness about everything--losing a lucrative career in the NHL is bad by itself, but losing one's saving-people vocation at the same time is even worse. He doesn't seem to be as simple as Kenny claims he is; he's certainly still strong enough, and at least somewhat smarter than the popular perception.
Perhaps he was forced out of the depressing-semi-real-world equivalent of the Justice League because of his head injury. Maybe that's why he's so angry.