Hi Sarah,
If you had all of these together, that is the main problem. When you breed birds, you have to remove the chicks from the parents as soon as they are weaned. The parents instinctively try to drive the chicks away. This prevents inbreeding in the wild. As for breeding them, you can only have one pair in a cage for breeding, and no other birds in the cage. Since this pair had already bred, the male naturally doesn’t want other birds around his mate, even if you decided to stop breeding and took the nest away. Once adult birds bond, they no longer have physical contact with other birds. They may live in a flock for protection, but each pair keeps their distance from other pairs. Most likely the male didn’t like other birds around his mate, and when he couldn’t make them go away, he turned on the female. In the wild, the male does this to make the female go back to the nest while he drives off the intruders. Your male is in a situation where he can’t drive off the intruders, or his offspring, or keep his mate to himself. Some birds can be put in a group cage even if they were breeders, but some never adjust to being around other birds and only want their mate. If you have any nests in the group cage, this contributes to the problem. They only need a nest for breeding and only if you only have one pair in the cage. Remove any nests and that will help a lot.
But as far as she goes, she should be with her mate if possible. Try having only them in a cage, away from the other birds, but no nest, and see if that works out. The other problem is having an odd number of birds together. They will form bonds, even if they are the same sex, and one odd bird gets left out and picked on. You have a pair and their chicks, but I don’t know who the other three birds are. But if the chicks are weaned, there is no reason for them to be with either of the parents. It’s always best to find homes for offspring, because it’s the parent’s instinct not to have them around.
Thanks for the update,
Brenda