Aki no uchi wa kuchikeru mono o hito mo sa wa waga sode to nomi omoikeru kana - Izumi Shikibu Nikki(English Translation & Meaning)

秋のうちはくちける物を人もさは
我袖とのみ思ひける哉

Roma-ji: Aki no uchi wa kuchikeru mono o hito mo sa wa waga sode to nomi omoikeru kana
English Translation: Through all the autumn
my own sleeves were rotting too;
so you, it seems,
thought only of your own sleeves
as the ones that wore away
Meaning: All through the autumn my sleeves were rotting with tears as well; did you think, then, that only your own sleeves were wasting away?
Commentary: 23 The Dawn Moon and the Jotted Verses

After the twentieth of the ninth month, waking to the dawn moon, the prince thought how long it had been since they had met and that she too must be watching this moon. Taking only his usual page boy, he went and had him knock at her gate. Izumi Shikibu happened to be lying awake, turning many things over in her mind; lately, perhaps because of the season, she had felt more forlorn than usual and given to melancholy. Wondering who it could be, she tried to wake the woman sleeping beside her to go and ask, but the woman would not get up. When at last she did, she stumbled about bumping into things, and meanwhile the knocking stopped. Had he gone home? He must think her a sound sleeper, she thought regretfully, and wondered who else had been lying awake as she was. The woman finally went out but found no one, and grumbled, "You must have imagined it. Waking people in the middle of the night," before going back to sleep. Izumi Shikibu stayed up gazing at the misty sky until dawn, and when it grew light she began writing down the thoughts that had come to her in those early hours. Just then a letter came from the prince as usual.
The woman is Izumi Shikibu, daughter of Ōe no Masamune and, as the wife of Tachibana no Michisada, Governor of Izumi, mother of Koshikibu no Naishi. The Prince of the Dazaifu is Prince Atsumichi, fourth son of Emperor Reizei, so called because he served as Governor-General of the Dazaifu.
Izumi Shikibu's jottings written at dawn arrived just as they were by way of reply. The prince felt they had not been written in vain, and hurrying to reach her while she was still lost in thought, he quickly wrote back. This poem answers her "Aki no uchi ni kuchihatenubeku kotowari no ame ni tare ka sode o karamashi."
She was still gazing outside when his reply came, surprisingly fast, and she opened it in astonishment. In it were five poems, each answering one of the poems in her jottings.

The opening lines mean "through the autumn my sleeves were rotting too," taking up her "rotting away within the autumn," with an adversative particle.
The remaining lines mean "you too thought them only your own sleeves," closing in an exclamation. To her lament of having no sleeves to borrow, he answers that his sleeves too were rotting with tears, assuring her that she is not alone in her loneliness.
Author: Prince Atsumichi
Source: Izumi Shikibu Nikki
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