I want to foster cats, but am trying to figure out how not to emotionally injure them in the long run. Depending on the individual, the pain of abandonment by someone you love, is worse than the pain of living in a cage. How am I going to keep them from bonding to me? I can't adopt every cat I foster.
I think Chelle Gordon has the best answer, in that younger kittens are not yet bonded. It would be a sin for those that have been bonded for years to be separated.
There are felines that bond for life (Caring for a Serval Cat as an Exotic Pet), who will have difficulty bonding again if re-homed. Also some felines that form life-long coalitions, such as lions and cheetahs.
Most humans don't understand cat's capacity for emotional attachment. Cats that have been abandoned, or even those that have been in foster homes, will always remember their previous owners.
I found this thread on Reddit:
In particular one post:
“We've had many cats over the years - ours and foster cats, but only 1 comes to mind for abandonment issues. He was dumped as a kitten, but was adopted by a neighbor. They had him for years and eventually they moved a couple towns over. A few years later, they had to move again and somehow he ended up not going with. Don't know if they dumped him or he ran. Anyway, he showed back up in the neighborhood and we took him in. It took us months to gain his trust enough to get him in the house, but he didn't bond with us. When my brother moved in, kitty bonded strongly to brother and did NOT take it well when brother joined the military - in kitty's mind he had been abandoned again. He'd run away for weeks at a time. When brother came home after training, kitty was LIVID with him, but eventually forgave him. They've been together since.”