You haven’t ruined it ☺! I’m no bonding expert, but sounds to me like she got territorial when they moved closer to get hutch, even though she’s new. Does can be very crabby when it comes to their personal space. I’m having a similar problem- we moved to a whole new house (not just for the rabbits lol- I’m crazy but not that bad yet!). It was going fine until my female bunny decided the cardboard hidey box was for her alone, and began popping out and going after her little husbun whenever he came near. Ugh, so frustrating.

If I were you, I’d go back to the upstairs bedroom, if you haven’t already. If they are still fighting, a break for a few days or a week might help. Once you get that back to the point where you’re ready to go back near the hutches, I would give everything a thorough cleaning with vinegar, maybe put down some cheap new rugs, just make the place as unfamiliar as possible. Hopefully that will help. I get what you’re going through- bunnies are so hard to figure out, and it’s scary when they fight! My boy bunny scratched my lady bun when I first brought them home and they got together accidentally, and she needed to go for stitches! Ever since then I’ve just been off the chain about any type of aggression. But some nipping, humping, lunging and fur pulling is normal. It’s just telling when it’s getting too serious, that to me is the hard part.

Good luck and please keep us posted!