Cloudy Eye in one eyed Cat
 

You want others to tell you what to do...but if you have a pet, it's
your responsibility. I took my Molly to the vet when one of her
beautiful brown eyes got spotted, she had a tumor, at the time it had
not spread, so she had surgery, because the Vet determined it was ok, no
cancer in any other part of her body.
A veterinarian will do only so much, a cat cancer patient will get one
dose of chemo; after that...it's up to you to do the right thing for
your pet. The animal is their patient; your issues are your own, a
responsible Vet will not have a pet lingering in pain because of the
owner.
A year later, our gorgeous black velvet Molly, almost 5 ft. tall on her
hind feet, started to fail, stopped eatiing, lost 33% of her body
weight in 1 month. Thankfully, she was a cat, she let me know when it
was time, I didn't have to make the decision. The cancer had spread to
her liver, her tummy...it was time to let her go.

If you can't pay your pet's freight, don't have one. If your blind cats
are fine with it...who are we to judge. Just watch them, and love them,
don't keep them just for you.