The news came by Hellmoth mail. At first he didn't really get it, and his eyes would skim over and over and over the words without fully understanding their meaning at all. Then realization came- she was getting married.
Kuchiki Rukia was going to marry Abarai Renji in a month. Rukia was going to get married.
After Aizen's defeat Rukia chose, once again, to stay at Soul Society. Byakuya had been severely injured in the final battle and it was her duty to take care of her Nii-Sama. It wasn't as if the cold-hearted bastard deserved any of that from her, or at least that's what he thought. But saying that aloud only got him a punch to the stomach and long diatribe on the virtues and merits of the Kuchiki clan's head, from a very irate black-haired shinigami. Still, Ichigo couldn't completely forget the fact that Rukia could've been dead (reincarnated, whatever) right now, she could've been executed three years ago, and her brother wouldn't have moved a finger to help, hadn't Ichigo pounded some sense into this thick skull with the help of Zangetsu.
She would visit often enough, she had duties as an officer of her division and had to patrol Karakura town in search of hollows, the few ones that had lingered after the Hueco Mundo battle. He still helped her every time she came, and she would stay (sometimes days, sometimes hours) and hang with him and Inoue, Chad, Ishida and even Kon and Urahara.
Then the attacks stopped, apparently they had been more than efficient in their extermination of hollows, and she had no more reasons to visit. Despite the fact that they had been friends for almost five years at the time, there was a gap that couldn't be breached that easily. She was a shinigami and he was a human boy (a human boy that had defeated hollows, bountos, arrancars and a delusional wannabe God, but a human in the end).
They didn't talk about what'd happen then, they both knew. There was no goodbye, as they already had had their share of farewells and this, the definitive one, would be too painful to survive.
Ichigo knew he loved her. At first he had thought it was just respect, admiration, deep friendship; she had changed his world, had given him the powers to protect his family, had made the rain stop and shaken him when it threatened to return. On their first trip to Hueco Mundo, he realized he was fooling himself.
They went there to save Inoue from Aizen's clutch, just like they had gone to Soul Society to rescue Rukia from execution. So why couldn't he focus on Orihime? Why was he always worried about Rukia, instead? Why had he accepted the fool's decision to take separate paths? Why had he returned to her aid (although she had already defeated the hollow form of Kaien) instead of gone directly to the palace? The answer slapped him hard after it was all over.
They hadn't confessed their feelings; there was no need when they'd show them in every action, in every touch and in every look. There was no need when he already knew she would never stay with him (nor he would go with her). The words would just hurt both of them.
He wouldn't attend the ceremony, what was the point? And it had been years since his last visit to Soul Society, anyway. But he'd be sure to pray for her happiness that day.
After the day of the wedding, Ichigo didn't feel angry or sad anymore. After all, he now understood the workings of the universe; one day they'd be together again, whether in Soul Society, Earth or Heaven (maybe Hell?) and when that time came no one would be able to rip them apart again.
Until that day, he will only pray for one thing for himself: patience.