Forever Knight.S2E23.Be My Valentine

Forever Knight is a 1992 - 1996 Canadian television series about Nick Knight (Geraint Wyn Davies), an 800-year-old vampire working as a police detective in modern-day Toronto, Ontario. Wracked with guilt for centuries of killing others, he seeks redemption by working as a homicide detective on the night shift while struggling to find a way to become human again.
S2E23 - Be My Valentine
While tormenting his protege on the hunt for a Valentine's Day killer, LaCroix remembers a bittersweet lost love, Nick's mortal sister Fleur.

Aka. Bis der Tod euch Scheidet (Until Death Do You Part)

Guest Starring:
Claire Rankin (Fleur)

Cast:
Marvin Karon (Stan)
Nonnie Griffin (Nick's Mother)
Natalie Gray (Terry)
Patricia Carroll Brown (Elsa)
David Sutcliffe (Fiance)
Shelly Hong (Coed)

Written by Diane Cary
Directed by Stefan Scaini