Little blind house finch

I've got the saddest little bird at my finch feeder. Little female house finch who's very obviously blind either from injury or illness. She's been sitting at the feeder for a very long time, feeling a little secure of food because she can feel around with her beak to find the hole for the thistle seeds. I can't believe she's as big as she is, but this may be a new thing and not something she was born with. Don't know quite what to do about her...she can't see me so I can walk very quietly right up to her. If she can find the birdbath (just below her) she may be okay for a bit anyway. If she's startled, she doesn't fly, but stretches up as tall as she can, on guard for whatever it might be.
Later... Contacted a lady who works with Tracy Aviary and she said it's got house finch conjunctivitis--extremely contagious. I've got to catch it (just my luck, after two hours on the feeder, it just flew off--awkwardly trying to find a branch) and take it in to be put down. Then I've got to disinfect both my feeders as that's where it spreads.