a patient
A person who makes your life a living hell. They book appointments, cancel them, then yell at you for not showing up. They’re the worst kind of person who ever lived.
'That patient called in, then didn’t show up, then yelled at me for not showing up.'
'He’s a patient, and he’s the reason I want to quit my job.'
'She’s a patient, and she’s the worst one we’ve had in a decade.'