carry a torch for
US /ˈkæri ə tɔːrtʃ fɔːr/
UK /ˈkæri ə tɔːrtʃ fɔːr/

1.
garder une flamme pour, avoir le béguin pour
to have strong feelings of love for someone, especially someone who does not feel the same way about you
:
•
He still carries a torch for his ex-girlfriend, even though she's married now.
Il garde toujours une flamme pour son ex-petite amie, même si elle est mariée maintenant.
•
She's been carrying a torch for him since high school, but he never noticed.
Elle garde une flamme pour lui depuis le lycée, mais il ne l'a jamais remarqué.