Even when I'm holding her, she is CONSTANTLY preening. She even will pester me until I preen her neck and if I stop she gets quite mad.
I'm really at a loss. She is 4 years old and this is kind of a new thing. I do go to school from about 9-4, except when I work and I'm gone for 12 hours. She has never minded though. I have had her since 4 months old, I did move a while back in January, but honestly I thought it would be better. Before she was at my house with my mother and her children like to bother her constantly. Now around the same time I moved I got 2 other Grey's. I inherited them from a customer at work who was going into a nursing home. I tried to get them acclimated, but they both hate her. She is a really, really, tiny Congo and they're both a bit bigger. I do not have them here for a bunch of different unrelated circumstances. I also thought maybe it's because she is a bit hormonal and she wants to breed. She's been doing the throwing up thing a bit more and always wants me to give her food/water from my mouth while I'm eating...
I have tried so many things and I'm just lost as to how to get her to stop.
She eats Pelleted Food (Zupreem), Random fruits, and occasionally I give her oatmeal when I eat it for breakfast. I took her to an avian vet and she has no parasites, normal weight as well.
She has a quite large cage that I actually leave open unless I'm not here. I moved her cage into another room that has more light, but is farther away from me walking by. She has 6 toys, none of which she uses, even though they're different kinds. She also has two foraging toys I put random things in. At the bottom of her cage I use carefresh, but she doesn't ever mess with it. I bought anti-feather picking spray, but it smells like alcohol and I don't like the idea of her inhaling that.
The only other idea I have is maybe I need to bring one of my other Grey's here. I recently left for 2 months to do some research in Malaysia and I had my friend bring my other boy grey (Aslan) here as well as her birds. She actually slowed down on the chest picking during this time.
I also heard some people use Palm Oil occasionally? I also started leaving the radio on when I leave, but I get worried about what she is listening too. (I'm weird I know) Or maybe she has allergies?
So with all that being said, does ANYONE have suggestions on how to combat this problem?
**Edit**
Added some pictures



How She looked before






