Thirst
(2009)

Priest Sang-hyoen becomes a vampire after a transfusion during a medical experiment.

Sang-hyoen falls in love with Tae-ju and is tricked into killing her husband thinking he's saving her from abuse. When she accidentally lets the truth slip he kills her in anger, only to bring her back as a vampire.  He soon regrets his choice to bring her back when she begins enthusiastically killing innocent people to feed her thirst.

Unable to live with the guilt San-Hyoen takes Tae-ju and her vegetative state Mother-in-law to the coast where the two vampires die with the sunrise.

Thanks Robbie!