Oh my, I am so sorry thoughtless irresponsible people are doing this to you and to the poor kitties. And for the rescues to treat you so badly on top of it! That is horrible!
There are idiots who think house cats can do fine “in the wild” or that “these people will be happy to get another barn cat”. No, house cats do not do fine after getting dumped. They starve, get attacked by other cats, coyotes, birds of prey, they freeze, get sick, etc. And those with barns already have the barn cats they want, and those cats do not take kindly to newcomers.
All they do is dump their problem on someone else — in this case, you.
Maybe there are Freeper in your area who would like to adopt the cats you still have? It would not hurt to ask. Lots of cat lovers here. I pray you find a good solution very soon.
My youngest babies are 7 and very afraid of strangers. Adoption is unlikely. I just do the best that I can and hope God provides what I can't. :-)