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The subject of intentional breeding or meat rabbits is prohibited. The answers provided on this board are for general guideline purposes only. The information is not intended to diagnose or treat your pet. It is your responsibility to assess the information being given and seek professional advice/second opinion from your veterinarian and/or qualified behaviorist.
I’m not sure what’s causing this either, but if absolutely everything is as it usually is (and has been) I can only think Lucky is maybe in discomfort of some sort…. and doesn’t want mo near her…. 
I know moults can cause personality changes in buns but to start attacking a bonded buddy? If that were the case I’m sure there wld be more posts about it….
I can understand you feeling helpless…. can you get her checked out by a vet, just in case? And don’t forget to take Mo with you !!
Keep us updated. Please. 