Disclaimer: I own nothing. If I did, I would have the money to buy all the bacon I wanted. But unfortunately, I don't. Therefore, I get no bacon.
1.) Lelouch learns of true loss at an age no child should. But what horrifies him, even as a child, is that his sister's fate is what truly gets to him - even as their mother's loss is a tragedy all by itself.
2.) Lelouch learns of losing one's home shortly thereafter, with hatred forever inscribing its curse upon a boy's heart. "One day, you will break the world, lest it breaks you."
3.) Lelouch learns of losing bitterness when, in those few, happy years, Nunnally and Suzaku are all that he needs in this new, strange world.
4.) Lelouch learns of losing faith in the honor and chivalry of others when the invading Britannian forces do not just invade the rechristened Area Eleven but instead wage a brutal, no-holds barred war on the civilian populace. Once more, hatred sears indelible words into his heart. "One day, millions will die because of the fetters you place upon yourself."
5.) Lelouch learns of losing one's inhibitions when, for the first time, he orders a group of men to kill themselves in order to protect himself from them. He never gives it a second thought why he did not simply compel their eternal obedience instead.
6.) Lelouch learns of losing a family member through his own hand. When Clovis' blood pools around his stolen army boots, vengeance etches its words onto his heart. "One day, you will find that despite all the deaths you cause, you love strife."
7.) Lelouch learns of losing a battle when facing his sister Cornelia. Were it not for CC, he would have died that day, and he knows it. In the constant verbal battles between him and his witch, this will, to their last days, remain a point in her favor.
8.) Lelouch learns of losing his fear of death the first time he puts a gun to his head to show CC the lengths he would be willing to go. Self-hatred carves its words into his skull. "Only those who are prepared to be killed should be allowed to kill."
9.) Losing the shroud of anonymity in the face of the world is the most exulting moment in his life to date as the Black Knights announce their claims to being allies of justice, defenders of the weak and punishers of the wicked.
10.) Losing to the damnable white Knightmare and, through that, losing the knowledge Cornelia possesses teaches Lelouch about frustration better than anything else could have done. When best laid plans get derailed by seeming acts of god, no man can do more than gnash his teeth, even as frustration chisels its words into Lelouch's mind. "One day, your plans will be unmade because refuse to do everything that is necessary."
11.) Lelouch learns of losing the mask that begins to replace the face when he unveils himself before Kirihara Taizo... all in the name of hatred and vengeance, who burn their words into his soul. "One day, your past will cause a tragedy that will break you."
12.) The loss of Shirley's father, caused by his own hands, is a shock to Lelouch. Killing faceless pilots and their knightmares comes easy to a man whose heart is barely more than obsidian, but the horrible, personal tragedy of losing a parent to an untimely death is something that touches his heart nonetheless.
13.) Watching Shirley lose her mind to the machinations of Mao the Mad almost breaks Lelouch's heart... and when he is forced to grant her the gentle bliss of ignorance through his geass, part of him dies that day. Anguish scratches its words onto the broken parts of a young man's soul. "One day, you will pay tenfold for all the suffering you have caused through you actions."
14.) The thought of losing his witch to Mao the Mad is most unpleasant. Lelouch learns the lesson that there are people in the world that are just as broken as he is... and it is CC that he thinks of, not Mao.
15.) The notion of losing his sister teaches him two things: First, that if he wants someone dead, he will shoot them himself, and second, that nothing is too much, no price too great, no action too hard to save her. Nunnally, more than anything else in the world, is why Lelouch and Zero live. The words of love itself strengthen his spine. "One day, others will truly love not just for who or what you are, but for what you will do."
16.) Losing any possibility of enlisting the one man in the world he thought he could entrust his beloved Nunnally eclipses the momentary triumph of recruiting Japan's greatest general. No man is worth leaving Nunnally unguarded for.
17.) On that day, Lelouch learns that his plans go awry because he refuses to do what is necessary. Ordering Suzaku to live instead of ordering to save both himself and Zero will haunt him for a very, very long time. Exasperation claws its words into Lelouch. "One day, you will turn even your greatest mistakes into weapons to wield."
18.) Talking to Euphemia on that wretches island reminds him of everything he lost since his mother died, but Lelouch learns from this that Nunnally is not the only family member in this world that he well and truly loves. Her words calm the raging fires within him just as her every action heals the scars of a lifetime of vengeance.
19.) Losing Euphemia, however, is something different. Peace, sweet, blessed peace, so close at hand, undone through is own folly and the cruel laughter of fate forcing misery upon him. As he shoots that angel of peace, Lelouch dies. What is left is an automaton with crystal clarity, infinite focus and neither heart nor soul.
And on that day, Lelouch loses himself.