It sounds like she is reacting to the smell of the new bunny? And possibly having hormone fluctuations relating to being spayed, depending on the timing?
Female rabbits can go through a post-spay “craze” around 4-6 weeks after spaying, but it should calm down after that.
Both things should get better with time. Rabbits that were overly caged can tend to get cage aggressive, it will probably help to not clean her cage or rearrange things while she is in it. So, if you can avoid messing with her “stuff” while she is in her cage, that will help. If you must mess with things, I find it helps to actually tell the bunny “excuse me, just going to grab your water bowl” or whatever. It sounds really silly, but I think sometimes they get startled by a hand reaching in, so saying something lets them know you are not trying to sneak up on them.
If it’s more related to a new bunny around, then that should also calm down with time. So just try to be patient and stay calm. When she lunges at you, try not to flinch if you can (wear gloves if needed). I’ve dealt with similar rabbits while volunteering at the rescue, and my strategy is to have my hand kind of mimic the shape of a rabbit head (make a little fist, so your knuckles face the bun). When they lunge, kind of curl your hand up and pet the top of her head. That mimics another rabbit grooming her. In time you might find she lunges at you for pets 🙂
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The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.