Do these lunges end up as full-on fights? If not, to me that just sounds like normal bonding :? I assume you're giving them dates, how long do you leave them together? Personally I'm not a fan of dating, every time they're separated things go back to square one. They need time to figure each other out and sort out dominance. My pair have been together for a month, they still have the odd chase and grunt, and a few weeks ago they had a bit of a bad scuffle but it doesn't seem to have affected their bond at all. Maybe try leave them together longer? Let them get to know each other properly.
Oh my goodness!
You and I must be old school! When I kept rabbits years ago, and was known as the local rabbit lady, another would come to us and it would be "look everyone! a new buddy!" and in they'd go and everyone would circle and thump and there'd be a minor scuffle and some would give the other the stink eye, and they'd sort it out and in a couple days they were lying in piles on top of one another or the new guy was getting the fur licked off his head by 3 besotted females.
BUT, those were in outdoor conditions with real dirt to dig in, and grass to play in and all that good stuff.
Indoors with just two bunnies...apparently there is a whole dating ritual more complex than that of humans.
I signed a contract that I would do the bonding process according to the "rules", and that if she comes back with a bite, scratch or hair missing from letting them work things out, I am fined $250, and they can call animal security to take my rabbit away. So I have read articles, watched videos etc etc to learn this new modern rabbit dating business.
The only time I had two rabbits who couldn't make friends was two males indoors. They would go out of their way to fight through the barriers to get at one another. It was madness.
So, even though it's not completely according to the rules, I have her in a pen, surrounded by another pen so they are in the same room but have several inches of clearance, otherwise they have tried to nip noses and scratch eyes. I figure they had better get used to sharing space, and the only other option is to have her locked in a room away from the family and that isn't good or happy for anyone.
The "dates" consist of the three of us going into neutral territory (hallway blocked off) and me petting each of them because without my hand on them they fight. We go nose to nose, all three of us, and have a bunny cuddle and lots of sweet talk. then I keep one bun calm and let the other hop about a bit and give us a sniff. The dates last anywhere from 20 minutes to an hour. I have not let them alone together at all without me being referee. I've had to break up some very angry scuffles. Never let it get out of hand at all.
I've tried having them eat greens side by side etc, she won't eat with him in the hallway, though he doesn't mind her presence. I've tried to get them to eat near one another with her in the pen, he's game but she feels pretty agressive. She stamps her foot at him a lot. He is a big baby and comes to me for comfort.
When I read articles saying this can go on for months, the idea is exhausting. If they hate each other that much....months of trauma seems like a lot to go through. Like I said, I never had this much trouble, but perhaps rabbits in groups are rather different than rabbits one on one.