Seeing your beloved bird pluck is so disheartening.
My cockatiel Indy first started plucking when he was very sick with fatty liver disease. He'd plucked his whole back and chest. A year and another vet visit and his liver has recovered, and most of his feathers have grown back, but maybe two or three times a day he'll pluck, and he usually screeches in pain when he does.
The vet thinks it may be either hormone related or habit related. I can't help but wonder if it is for attention, since he doesn't ever seem to pluck when we are away from home - just when we are in the room with him. He has a ton of toys that he LOVES to destroy, so it doesn't seem to be boredom. But I am not sure. I've been thinking I need to keep a log or something of every time I see him pluck to see if there is a pattern.
What species is your bird? How long have you had her? Have you visited an avian vet since she started plucking? In many cases, plucking can be a sign of illness. That's how Indy started plucking.
Edit: You also mentioned giving her meds. What kind of meds were these? I've used Avi calm for my birds, and it seems to help at least a little bit while still allowing my birds to act like themselves.