I think it's not surprising that after Shinichiro's death Rei was in a terrible mental state. At first, after what happened she couldn't even believe that Shinichiro was no longer around. She still felt like she could feel him around her, hear him. She would unconsciously start talking into the void when she wanted to tell Shinichiro something. She slept only on her side of the bed, placing Shinichiro's t-shirt on his side. She wrote to him constantly, refusing to accept the fact that she would never receive an answer. While she was in a state of shock, she still tried to live, she tried to take care of Manjiro and Emma, she knew that it was probably more difficult for them than for her. But over time, the realization came and it hit her with a new wave. Rei was deeply depressed. She stopped living. Just existing. She stopped eating normally, washing, taking care of herself, her hair was falling out from stress, her eyes were empty and her body lost weight. She suffered with nervous breakdowns and withnightmares. It got to the point where she began hallucinating Shinichiro, causing her to cry constantly. It was at that moment that she was left alone, with no one by her side. She stopped interacting with Shinichiro's siblings. Especially with Manjiro. She couldn't look into his eyes, which were the same as Shinichiro's. She was simply ashamed to show herself in front of Emma. They were worried about Rei too but no matter how hard they tried, she pushed them away painfully and in the end they gave up. The only one who remained in Rei's life was Wakasa. It so happened that during the most difficult period, it was her "enemy" who began to take care of her. Wakasa had a spare key to their house, so he would come over uninvited. He would buy groceries, cook, make her eat, take her outside, even wash her (not something erotic). No, there was no love between them. Wakasa wasn't her second chance at happiness. He helped her because he knew it would be Shinichiro's last wish. He felt indebted to his friend. And it was at that moment that Wakasa realized how strong their love was. Wakasa felt ashamed of his past behavior towards Rei. He was still rude to her but he still came for her, take care of her like she was a kid, make sure she was still alive. But one day he was late