I do sadly have a bully like that and I have done a number of things to reduce her bad behaviour so far it has only temporary fix it for a week, then back to her bad way again.
1 time I put her away for a long whole week, she can see the flock but can not get to them. She was so sad, she walked to me and looked up at at me, my heart just sunk into the abyss. How could I? I let her back in and after 3/4 days she was at it again. So back to being separated again.
Now I separate her 2/3 of the day every day....so far so good, but let see how long this last.