Cat's eye in very bad shape

My cat is 16 years old and she is a domestic short hair. On her left eye her "third eyelid" is showing in the bottom corner and in he upper corner there is a red swollen area. I took her to the vet and they think it may be a tumor that is pushing the eyelid in. She can't even close her eye, I don't know how she's supposed to sleep. Is anyone familiar with this? Here are some
pictures:
http://i1153.photobucket.com/albums/p520/josh70071/67648af2.jpg

http://i1153.photobucket.com/albums/p520/josh70071/52d4591a.jpg

I have seen many eye infections and yes, they can look like that. But your vet is saying that there is a tumor behind the eye? I guess I would get another opinion as it will be impossible for anyone to confirm this for you. What did your vet say the options are? Did you run any tests? Xrays confirming a tumor? I hope your girl feels better and can get something to make her eye feel better.

The vet doesn't know for sure. the cost of MRIs and stuff are very costly and may not be worth the trouble, because they may not be able to find a possible tumor. Her eye is very swollen now and she cant close it. i put her in her favorite chair a about 6 hours ago and she has been sleeping in it for a while. Do you have any idea what this actually is? Horner's Syndrome? Cherry eye? Haw Syndrome? Conjunctivitis?