He's been 'unlucky in love'. [=he has had a series of bad romantic relationships]
She was 'unlucky' enough to get a flat tire on the way to her job interview.
He thinks it's 'unlucky' to have a black cat cross your path.
(..) . . .you three. Ravenclaws, follow me. She's not dead, Argus. She has been Petrified. Thought so. So unlucky l wasn't there. l know exactly the countercurse that could've spared her. But how she has been Petrified, l cannot say. Ask him. (..)2002 Harry Potter and the Chamber of Secrets