HELP! Pet lovebird keeps 'preening'/nibbling me!

[Rayla]

Hello! Recently my peach faced lovebird (Mochi) has been nibbling on my neck and hands, this started roughly 2 weeks ago. At first it started when she would be sitting on my shoulder or she would come over to my hands when Im at the computer. She would almost lightly nibble at my skin. I would let her know when it hurt with a slight screech and then set her down if necessary. We have a great bond and I know she's not biting me out of anger but I seriously don't know what to do. As of now my neck and hands are covered in small red marks left behind from the small bites (photos listed below) and my skin is starting to become raw. It almost feels as if Mochi is becoming obsessive over nibbling. I could distract her with something and she would ignore it and climb right back up. It is also obsessive in the sense that she is over preening even if I was another bird. Over the last week and a half I've been following different web forums and solutions that I found regarding similar situations. I have tried imitating a birds chirp that they make when something hurts, I've tried removing shoulder privileges when I found necessary, but nothing seems to work. I don't want to put her in her cage and end up making her hate her own safe space. Please let me know what I can do!

Bird Background: She is about 5 months old and I have given her a variety of shredding toys and other necessities in her cage. Since I am a college student I'm mostly home and let her have plenty of play time and interaction. I also make sure she is given a good diet including a variety of veggies, fruits, legumes, pellets, etc. I also help her with pin feathers that she can't reach. She has interacted with other parrots in the past before I got her and enjoyed preening the back of their necks.