An "unrequited crush" refers to having romantic feelings for someone who does not feel the same way about you. It means that your feelings are not reciprocated. Full definition
As James, who has a persistent and unrequited crush on Mildred, he's soulful and tart and inventive. (washingtonpost.com)
While the story is being penned by Tania del Rio, who said she's filling the book with humorous entries focusing on all the drama of being a teen: «Academic pressure, the highs and lows of unrequited crushes, «frenemies» and trying to balance growing up with keeping childlike interests.» (goodereader.com)
We always know what's at stake, whether it's the memory of Erik's mother, or Raven's unrequited crush on Xavier. (combustiblecelluloid.com)