Rabbits do not really need companions, if you are willing to take time with them – after all, you got it as a companion for yourself, not so?. They are by nature very territorial , although the spaying does seem to make them a bit more tolerant of invaders. In my 30 plus years of breeding, I have observed more problems and deaths through combined caging than any other factor.
I do know that there are two schools of thought on this, but I do believe that ignorance and regarding of rabbits as pack or herd animals, instead of colony animals does lead to confusion.
Pack animals rely on each other for active defence or attack to a mutual benefit, and do form bonds for their survival – a classic is our lion prides, where all the females are related, and have very close bonds to ensure the survival of all.
A herd of horses, is another classic, where the mares will guard their own foals, and the stallion will guard against predators. However, when a herd member is killed by a predator, the herd does not try and protect it, they simply move off and leave the remains for the predator to consume.
Basically colony animals group together with no real bonds, they are prey animals, and by being in a group they may confuse predators, thereby having a higher survival rate. The colony of rabbits scatters to the winds at the first sign of danger, and the predator takes the hindermost.
Now please remember, that there are exceptions to every rule, from foal killing stallions to close buddy bunnies, but I am talking about the norm at this stage.J