Male finch wont let mother in nest aggressive

Question
I have a make and female zebra. They were getting along fine and had laid four eggs in the first clutch, but they didn't make it. Recently, I found five eggs in the nest and they were parenting well together taking turns in the nest or both in together. Yesterday, the male started getting very aggressive with the female. He wouldn't let her in the nest and would attack her if she came in. He got so aggressive that I am now in the process of separating him from the female and eggs. The mother is afraid now and hasn't gone in nest for about two hours. What to do please?

Answer
It sounds like the male either has very strong protective instincts or just doesn't like the female sitting in the nest because then she doesn't want to mate. Separating the two was the right idea but getting a completely new nest might be the only way to go