I did separate them once, briefly. One of my other females, Joan, was crying for a mate for, like, three days. Nonstop crying day and night. It was torture. So i switched Joan and Violet for a few minutes to see if maybe Neil would accept her. Three things happened:
-Neil freaked out and ignored Joan and ran around his cage calling for Violet.
-Whenever Joan got near him, Neil would attack her by grabbing her neck feathers like he was going to mate and then just stepping on her.
-Violet, in the pen with the other girls, became so upset that she threw up on herself and then laid down in a corner with her face pressed against the side of the pen and closed her eyes like she was dying.
After five minutes, i realized that this was not going to work out and i switched them back. Violet immediately popped back to life. She pecked Neil in the head very hard (like it was HIS fault) until he laid on the ground and let her stand on him, and then they spent the rest of the afternoon preening and snuggling. I felt super bad about not taking their commitment seriously and i won't separate them again.