If you have a spare tank you could try isolating the Purpuratus for awhile and return him to your tank in a couple of weeks to see if he is less aggressive when he is not mating. May or may not work, but worth considering. I would definitely rehome the Auratus as they are naturally super-aggressive and less valuable than the fish she is bullying and stressing out.
I currently have a 5 plus inch male Auratus which I rescued a couple of years ago. He has spent the last 2 years in a 90 gallon
Oddball tank filled with other very tough African mbuna, a 9 inch Blackbelt and an 11 inch female Oscar. Managing his aggression is not easy, and he wreaked absolute havoc and terror in my 125 gallon tank full of larger Haps and Peacocks when I initially tried to home him there. I had to remove him after only 24 hours, or I would have had some much more valuable cichlids killed by him. His attacks on every other cichlid were relentless.
He is not the boss in my 90 gallon but he is constantly challenging a similar sized OB male mbuna who fortunately is a better fighter and is not inclined to kill the ungrateful, ever- scheming Auratus. 🤔The Blackbelt also helps check the Auratus when he starts to go berserk. The Auratus and the Oscar ignore each other, whereas the Blackbelt and Oscar have been best buddies for years.
My point for all this, is that Auratus are beautiful but very difficult fish to accommodate.