[Sycohearted]

My cat, Willow is very old...and due to my parents negligence she has not been to the vet in over 10 years and since her age is catching up with her, she is becoming very sick(?)
I am asking this because we do not have the money to take her to the vet...I want someone's professional opinion on this.
Please note, I love my animals very much...I want to know if I should get her put down or keep saving my money to eventually take her to the vet?
My final option is to take her to a Cat-Haven in my town who can take her of her until she passes...
But I do not want to milk her life if it is thought that she is in pain. Plus this breaks my heart because I want her ashes...All in all, I don't want to be selfish with keeping her alive.

Her symptoms:
-Pulling her fur out
-Twitching and fidgeting and constant moving. Like when you toss and turn in bed to try and get comfy?
-Sitting on her tail?...
-Incredibly skinny
-Licking herself constantly
-Urinating and defecating on furniture and floors.


PLEASE NO RUDE COMMENTS ...It was never my choice for whether my animals went to the vet or not, If it WAS my choice, my cat would of been at the vet every month...My parents take our dogs every month, but always told me "the cats do not need vet treatment"...I hate my parents for this but since Willow is behind on so many shots, They don't even want to imagine what the bill would be.
They will only pay to allow her to be put down...
Please, what should I do?... Do I put my dear cat down or send her off for someone else to pay the bill (Which I feel horribly guilty to do...)