Finally I hit her back - Please advice?

I can understand everyone has their boiling point, just because you're a guy doesn't mean you're a monster for hitting her back but it is bad because males are naturally much stronger than females and it is an unfair fight. So I think this could be held against you. But she sounds incredibly unstable and I'd be very afraid to have her have custody of your child... You should figure that out in time for the divorce because perhaps you should have custody.