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I have had my cat for a very long time, her behaviour towards people is antisocial but to me she is very lovable and is always sleeping by me and cuddling. for the past few days she has been eating and drinking a lot less, I have tried to give her treats ( which she loves) and she won't even touch them. I also noticed she has been hiding under my bed a lot and won't come out, whenever I try to cuddle with her she seems disinterested. This behavior is very odd she has never been like this. she often acts paranoid for no reason.
for reference my cat is indoor but sometimes will go outside and she is 10 years old.