Their last words to each other still haunted her at times. Happily married to the man she could honestly say was the love of her life, Lily could still truthfully say that she missed him. That sometimes, the urge to see him, to try to talk sense into him, was overwhelming. He had been her best friend since they were nine years old. And then Fifth Year had happened.
"I don't need help from filthy little Mudbloods like her!"
That had hurt. Deeply. They didn't talk anymore, but Lily had still hoped that something of her best friend remained free of the influence of the young Death Eaters. She had been wrong. Whatever remained of the boy she had known was gone. Sometimes she wondered. She wondered if he had left the house in Spinner's End; they, she knew, would never stop arguing, no matter what Severus said (or didn't say). Her heart ached for the little boy she had known as a child, who spoke of magic as if it were real. Twelve years later, Lily Potter missed her best friend. It was (fairly) easy to stay in contact with the 'Marauders', as they continued to call themselves; other friends who were also in hiding were nearly impossible to communicate with.
Lily loved James. Unreservedly, unabashedly, utterly in love. She still cringed whenever she remembered how poorly he had Severus in their youth, but she tried to move on from that. Some people just weren't meant to get along. She herself was a prime example; her own sister had cut off ties with her. But with Severus… Severus had understood her where Petunia had never tried. Severus understood her in some ways that even James failed to grasp. She loved James dearly, but there was a part of her that was innately understood by Severus, partially because they had known each other so long. She missed her best friend.
James, amazingly, understood. He tried his best to, at any rate. He couldn't imagine Sirius doing the things to him that Snape had done to her, but he sympathized with Lily. He had never felt anything but contempt and disgust for Snape, but Lily had, at one time, seen a hint of decency in him. The Marauders held a friendship so deeply revered that to have your closest friend treat you so poorly, so inhumanely, was not something that James would ever be able to truly comprehend; Snape had never held his respect, and he had hurt Lily. The cut of their friendship had affected her more than she let on. Sometimes, James wondered if it was best that Lily was intent on never mentioning her former best friend ever again. He wondered if it might be beneficial for her to have a closing conversation, though he knew that, with the fiery temper that matched her wild hair, she would not leave unscathed. Emotionally, possibly physically. Snape was, after all, a Death Eater.
They were next. He knew with certainty that the Dark Lord meant to target the son of Lily Evans. His chest still hurt when he thought of her. He had never meant to put her in harm's way. He knew why she had stopped being his friend. What he didn't understand is why he had stopped being hers. Why he had gone so willingly to fight for the very people who wanted all like her exterminated. As if they were vermin. Lily had been his best friend, his only friend as a child. He loved her. If he had not been such a coward, if he had not followed the older Slytherins into the Dark Lord's path, there was the slightest possibility that they may still have been friends. His heart ached whenever that thought crossed his mind; had he not become a Death Eater, she might have had a chance to live her life, she might have still been his friend, she might not have… even now, he had difficulty coming to terms with how their lives had diverged and the choices that had led them here. He missed what might have been, he missed her.