I just lost my very beloved barn cat to a suspected coyote attack.
It really sucks. He was a feral cat not deemed suitable for a home and he went from hissing at me for weeks to a total cuddly love...with a wild wall climbing streak.
He knew love, friendship, a warm bed and a full belly but the guilt I have is all consuming. He lived a great life but man...my barn feels very sad and quiet these days.
It really sounds like you gave him a great life that nobody else would have. Without you they would have died a feral cat only knowing struggle within the unending fight for food and warmth. With you they got to know love and got to leave all that struggle behind. You did good.