Unrequited love

Unreciprocated love

Unrequited love or one-sided love is love that is not openly reciprocated or understood as such by the beloved. The beloved may not be aware of the admirer's deep and pure affection, or may consciously reject it. Merriam-Webster defines unrequited as "not reciprocated or returned in kind".

Psychiatrist Eric Berne states in his book Sex in Human Loving that "Some say that one-sided love is better than none, but like half a loaf of bread, it is likely to grow hard and moldy sooner." However, the philosopher Friedrich Nietzsche contends that "indispensable...to the lover is his unrequited love, which he would at no price relinquish for a state of indifference." Unrequited love stands in contrast to redamancy, the act of reciprocal love.

Source: Wikipedia

One of the principal problems explored in the arts and especially in popular music.
(F) Fuzzy exceptional problems