It was just like being gently roused from a dream, and suddenly Lily found herself back in the world of the living. There was familiarity to her surroundings, as if they had existed in some long-lost memory that was so faint it might have been a dream. Yet she knew that she did not belong here; it was a truth she knew surely in her heart. She could not feel the thin blades of grass under her feet, even though she could see them there, and there was no dewy, earthy smell surrounding her in the dense trees. Was she half-here, or was this only a half-world? She couldn't tell, and it didn't matter so much, really.
She was here for a purpose, and it was that purpose alone which gave her a temporary window into her old world; it was what shaped her, what gave her all thought and action. Just as she had once given her son life, he was now her own lifeline. It was his thoughts and desires—ones conscious and otherwise—which had brought her here, and which influenced her now. She was not herself, but the collection of all her son's imagined notions about herself, about what a mother should be, and it was upon those notions that she existed now.
The world seemed to crash in on itself as her eyes fell on James, but she knew that it was their son who was feeling this heart-stoppingly intense emotion, reflecting it on her. James had always been with her. He was a part of her, and in the place they both inhabited—a place that was beyond speech, beyond thought, beyond action, and only about being in the most basic of ways—their being together was uncomplicated and blissful.
She felt his presence always, in every moment, and so seeing him in front of her was no revelation. He looked as he always had. His mouth was the one that had smirked at her, and that she had kissed; his eyes were those that had looked upon her with great tenderness; his hands were the same that had enclosed hers. But beyond here, she had the real James in her every waking moment. Being here made her feel like she had lost him, and at some level, she felt herself being torn apart. She was fleetingly brought back to those horrible last minutes of life, praying that the man she loved was unhurt even when she knew it was impossible.
Those feelings of horrible pain and loss collided with the joy emanating from her son, whose life and energy drew her to him like a moth to a flame.
And for the very first time, she laid her eyes on the man that her son had become.
He was weary; that much she could see as well as feel. There was a deep and meaningful sense of resignation about him that Lily recognized. His feelings of love and amazement filled her up, so much so that she remembered for the briefest of seconds what it was like to live again. She remembered the keen feeling of living emotion, the changes from one moment to the next, inspiration, optimism, enthusiasm, excitement. She was happy in death, happier, perhaps, than she had ever been in life, but there were no shades to her happiness. And as quickly as the remembrance had come, it left her. It was not for the dead to know anything of life, just as it was not for the living to know anything of death.
She would never know those feelings again, and she would never see her son again. He would be with her, and together with James they would finally be a family again, but she would never look upon Harry's features except in this moment. She wanted his image to take root in her mind, but whether she would even remember it once her time here was done, she could not say.
She could have spent a century memorizing every line of his features, but she had to remind herself that there was urgency to this world. How could she ever tell him all she felt, and all he needed to hear, in such a short time? She found that she did not know how to be his mother, not after all this time—she and James had hardly felt like parents in the first place, so briefly had that been their lot in life. Now her son was grown, and she had lost all the chances that would have taught her how to be the mother he needed.
"You've been so brave," she told him. The words felt lacking and almost child-like to her, but those were the words she thought of. It was the first time she had voiced how she had always felt about him through the connection that had linked them across worlds. She was proud of him, and she recalled what that felt like. And Harry, she knew, had wanted to hear her say so for as long as he had lived.
It was all she could say, and all she needed to say. Rather than speaking, she observed as Harry, James, Sirius, and Remus conversed.
It could have been like this every day, she thought to herself.
There was a growing sense of despair and bitterness in her, fed by the loss of the life that could have been. With every second they stood in the trees, her assured acceptance of her separation from this world faltered more and more. She began to remember what those shades of happiness were like: not feel them, but remember them. She wanted the chance to feel again, really feel, and now it was the world beyond this one that seemed to grow faint in comparison, as if someone had moved a magnifying glass from that existence on to this one.
The bitterness grew to a yearning so strong that she was almost moved to speak to Harry, to convince him to keep them there always, to not make her leave him again. If she asked, she knew that he would not be able to turn her away; it was hard even to know whether this yearning was her own, or had come to him through her. She could be part of the world again, as much as she could be, and perhaps she would eventually feel no different than she once had. Blades of grass tickled her feet as they moved through the forest. Harry could have his mother again.
Now they were in a large clearing, and Lily saw gathered there people who she had fought with, run from, chased down, and one who she had given up her life to. Her son was feeling that same determined sense of sacrifice that she had so many years ago, and for a moment, she was back in a second-floor bedroom, not in a forest clearing.
This unnatural yearning was almost enough to smother all other considerations—almost. It was that idea of being a mother that fought its way to the forefront. As a mother, she wanted to call out and stop him; she had once given her own life to protect his, and letting him be killed, even if it was what he had to do, did not feel right. And, as a mother, she also knew that she could not stop him from doing this, or put on him the burden of keeping her in this world.
She gathered what willpower she possessed, reminded herself that she would soon be happy again. She was returning to where she belonged. No one but her, James, Sirus, and Remus saw the small stone fall from Harry's hand.
It was just like drifting back into sleep.
*Bolded line is taken from page 560 of Harry Potter and the Deathly Hallows, UK edition