his/her ex
He misses his ex.
Elle travaille pour son ex, elle sort le soir pour le voir.
She works for her ex; she goes out at night to see him.
— La Mouche (1986)
Ce matin, il ne se rappelle plus de la dernière fois qu'il a vu son ex.
This morning, he can no longer remember the last time he saw his ex.
— It's Such a Beautiful Day (2012)