unrequited

yksipuolinen unanswered Unanswered; not returned; not reciprocated; not repaid.
1820, w:Sir_Walter_Scott Sir Walter Scott, The Monastery, ch. 20,

I stand on the privilege of a free Scotchman, and will brook no insult unreturned, and no injury unrequited.

One of my comrades there—another of those victims of eighteen years of unrequited toil and blighted hopes—was one of the gentlest spirits that ever bore its patient cross in a weary exile.

To her mind, a girl who would tell of the unrequited love of a man for herself, was unspeakably base.