Now at last I know
How bitter a thing it is
To wait for someone;
I should not have stayed away
From the place where one would wait.

Meaning

Now at last I truly understand how painful it is to wait for someone who does not come; I should not have kept away from the place where another was waiting.

Commentary

48. Now at Last I Know

A certain man planned to hold a farewell banquet for someone who was about to depart on a journey, and he waited, but that person did not come.
The poem was composed by the man who had been waiting to hold the banquet.

This poem is included in the Kokinshū, in the section “Miscellaneous, Part Two,” and in the headnote it is attributed to Ariwara no Narihira, stating that when Ki no Toshisada was appointed to Awa, a banquet was to be held, but even late into the night he did not appear.
Though it seems to be composed as if Narihira were admonishing himself, it can also be read as reproaching the discourtesy of not appearing at the farewell gathering that had been prepared.

Source

Ise Monogatari

Other

Now at last I know How bitter a thing it is To wait for someone; I should not have stayed away From the place where one would wait.

Now at last I know
How bitter a thing it is
To wait for someone;
I should not have stayed away
From the place where one would wait.