I guess you're disappointed too by Toei Tokusatsu's YouTube channel answer "At launch, we will have the first two episodes of all 70 shows available with English subtitles! Further episodes will be available in Japanese for now, but there could be frequent updates. We plan on making a public call for subtitles in any language." It's been 2 years and the remaining episodes haven't been released....
I think it has a happy ending. It's more of an open ending, but it hints at a happy ending. After all, Natsuko wishes for Kensaku to come home, and then a shooting star appears. Her wish will be granted.
However, it's bittersweet because their married life hasn't been very happy, and Natsuko can't turn back time and relive her life knowing what she knows now. However, I think it was a bit inappropriate of Marie to tell Natsuko that it was partially her fault, as she had closed her heart to her husband and driven him away. Kensaku should have communicated more with her during their 50 years of marriage. Natsuko gave him plenty of opportunities to warm up the mood between them. Instead of searching for stones all his life, he should have shared his actual life with her.
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It's been 2 years and the remaining episodes haven't been released....
However, it's bittersweet because their married life hasn't been very happy, and Natsuko can't turn back time and relive her life knowing what she knows now. However, I think it was a bit inappropriate of Marie to tell Natsuko that it was partially her fault, as she had closed her heart to her husband and driven him away. Kensaku should have communicated more with her during their 50 years of marriage. Natsuko gave him plenty of opportunities to warm up the mood between them. Instead of searching for stones all his life, he should have shared his actual life with her.