Bytheway, the summary is a lyric from Owl City's Tidal Wave. This oneshot below is the one that explains the AU that this series takes place in. Just a warning, it's VERY different from canon, though I tried not to stray too far from the time line itself. It's rather dark. The song lyric mentioned is from Down In Flames by Relient K.
To Edward Elric, the world revolves around his little brother. To him, it always has. (But he cannot stand the truth. So he buries it and lets himself be deceived.)
He does not remember his life before Alphonse was born. Why should he? It's just a year; surely nothing significant happened in that time frame. At least, nothing more important than Alphonse. (Oh, but he should have remembered that year. The last year his parents were ever happy. The last year he loved his father. The last year Van Hohenheim spent time with him.)
He does not remember the exact when and why behind their father's leaving. All he knows is that that incident made Al cry and therefore Ed hated their father. (May 18, 1901 is the when. Alphonse is the why.)
He does not remember crying when his mother died. But he knows Al did and that broke his heart. (He cried. He cried his heart out. Alphonse did not. He never realizes that Trisha didn't die of sickness. He never realizes she poisoned herself to get away from his little brother.)
He does not remember the exact moment he decided to bring his mother back- and he knows he shouldn't, that it's taboo. But it's for Al. Surely that makes it good, right? (But it's oh-so-wrong. Of course it's wrong, Alphonse suggested it.)
He does not remember why he wanted to learn on his own at first. But Al wanted a teacher, so he did too. (Because even as a child he subconsciously knew that whatever Alphonse learned would make him stronger. And that should not happen.)
He does not remember how they convinced Izumi Curtis to teach them. He still couldn't understand why she refused in the first place. (Because she saw Alphonse for what he really was. If not for Edward, she'd have avoided Alphonse like the plague. That or kill him, like Sig did to her first husband. She only agreed because Edward needed protection. He was blind to his brother's true nature, like she was to the demon she married before Sig.)
He does not remember why he insisted that Al not help him bring Mom back. It was because the process was dangerous and he didn't want to endanger both of them, wasn't it? (And he knew the consequences. He specifically remembered them from the talk he had with Izumi where she tried to discourage him from his goal.)
He does not remember Al protesting that decision. But surely he did? They're brothers, so Al wouldn't want to see him hurt the same way Ed wants to keep him safe, right? (Alphonse did not. He waited impatiently, knowing Edward would fail.)
He does not remember why he let himself be talked into the military. All he knows is that he and Al needed money and the State Alchemist status was the best source of income he could think of. (Izumi had a contact named Roy Mustang who explained it all to him. Alphonse was a demon that fed off pain. He latched onto one human. That one human drew people towards him. Those people did his bidding to keep the human safe. The more power they gave him, the safer Edward was. Why not give him access to the military? The country's power?)
He does not know why the war started. He just fights. (He doesn't know that Alphonse promises protection to Edward and those close to him as long as this war is fought. He doesn't see that Alphonse is growing soft. He can't see that Alphonse can't stand to watch Edward in pain. He has no idea that he's the sole reason that demons are dying out, being killed for daring to hurt the human that Alphonse has claimed as his own.)
The only thing Ed remembers from his childhood is a tune that Al used to hum. He does not know the words. ("We're cannibals; we watch our brothers fall. We eat our own, the bones and all.")