Face biting during bonding?
I'm new here, and I have a question about bonding. My six year old neutered dwarf, Spike, has recently lost his brother/bonded companion, and so we are 'fostering to adopt' a spayed female from the local shelter to see if we can bond her to him. We were preparing for a long haul, and so far we've been at it for only five days (which isn't very long at all), but the sessions have kind of been a disaster!
Spike, who is normally very social and interactive, seems terrified and remains glued to the floor, eyes bulging, and hyperventilating for all of each bonding session. And the new female incessantly bites him - mostly on the face. She's a bit overweight, and doesn't move too fast, and seems to come in calmly at first, but when she gets near his face (usually once every 30 seconds to minute or so during bonding) she bites his face quite hard. And twice today she almost got his eye... one time he squeaked and jumped back in pain and ran over to me thumping his foot, so I figured that was the end of the bonding session (we were only 2 minutes in).
He is free range, and the first few days she was here, he would sleep next to the cage and stick his nose in to say hi to her (and she would ignore him on the other side of the cage), but now he stays far away from her cage at all times.
I'm not sure what to do! I've tried smushed banana on the heads, honey on the noses, car rides, the washing machine, and 5 different neutral environments (I only live in a one bedroom apartment, so thinking of new places he hasn't been is getting tricky!). I'm not sure what else to try. Every bonding session is full of her biting him about the belly, and especially on the face - quite hard! Most of the time I manage to stop her, but I feel bad for poor Spike... he's just lost his life partner, and he doesn't deserve to be bullied.
Does anybody have any advice? I'm not sure what to do! The female rabbit is very sweet with me - she loves to be petted, and comes right up to me asking for attention, but with Spike it's like she's a different rabbit.
Any thoughts anyone might have would be greatly appreciated!