Need help/advice about pet.

My friend of 13 years has undergone a dramatic change in behavior lately. She is a mixed breed cat and has always been very affectionate
toward me, licks my hand, rubs against my leg, follows me everywhere, etc. We have long time established activities such as she would always sleep near my feet in bed, sit on my lap while watching TV, even curl up in my lap while I'm
on the computer. One long time practice was our taking walks together. She would paw the door and then jump on top of my recliner. When I got close enough she would stand and put her paws on my shoulder and I'd pick her up and carry her outside for our walk, during which time she'd lay across my arm and watch the sights.
The last two weeks or so she has stopped sleeping in bed by my feet. Now she sleeps in her carrier (which she's always hated because it means a trip to the vet), or under the bed. If I place her on the bed as before, she immediately jumps off and runs underneath. She won't sit next to me anymore and instead keeps a lot of space between us. She still acts like she wants to go on walks, but if I try to pick her up, she shrinks back and even hisses, but seconds later acts like she again wants to go for a walk. Activity between us is now very limited, she naps on top of the kitchen cabinets, literally as far from me as possible. Now when I'm on the computer, she lays by my feet, but avoids contact with me. She also sniffs everything I touch as if I'm a stranger to her. She even refused to get on the couch until I moved a pair of sweats off of it, prefering to lay on the newspapers underneath.
Sometimes she'll walk toward me like her old self, but at the last second turn away in another direction. She gives me the strangest looks, almost as if she doesn't know me.
I'm retired, so I'm with her 99% of the time as I have been for 6 years. Nothing traumatic has happened to her, she's strictly an indoor cat, up to date on all her vaccines. Her eating and activity level are the same. The only change in her environment is we're living in a new home we moved into on July 31st, which was more than 2 months ago and she seemed fine then.
I'm just really concerned at her being so off key. I'm planning a trip to the vets, but was hoping a fellow member might have some insight.
Any animal experts, vets, etc. out there?
Any help is deeply appreciated.

The first thing I would do is take her to the vet for a complete exam, just to rule out any medical problems.
Some cats, especially older ones don't adapt to major changes well, some older people are the same way when you think about it. Maybe shes just having a hard time adjusting to her new home?
If she has been with you for 13 years in the other home, she has probably become overwhelmed by the changes in the new home. Cats are very sensetive to scents or odors, it make take her a while to adjust to the smells of the new home. Have you painted things in the new home? The odor from the paint may be part of it. Carpets can hold odors that cats and dogs smell that we humans don't. If there were other pets in the new home before you moved in, they odors they left behind might be part of the problem. Try cleaning the carpet with the same products you used in the old home to bring the scent back to what she is familar with.
Do talk with your vet about the changes in her mood and behavior, he or she may have some other ideas as well.

+1 on what Rugergirl said. Cats especially are very picky with their routine. By chance have you started using a new shampoo, soap, deodorant? Have the manufacturers "improved" their product and added new ingredients or changed the scent of them? When I started working at a Jiffy Lube, I was coming home with new smells, my cats were not used to. It took the awhile for them to adjust and get back to their normal routines. Definitely get her checked out by the Vet. At 13 she's starting to get up there in age. Hopefully it's nothing serious, but you never know.

Good luck, from another cat person.

+1 on everything Rugergirl said. When I first read your post, I got the distinct impression that she isn't feeling well and wants to go to the vet. Going in her cat carrier to sleep and also getting your attention before hissing at you when you try to pick her up. These are good clues that she's not feeling well.

But taking into consideration all of the other clues she's giving you, it could very well be something scent or memory related. Either with the move or if you changed to a new soap, deodorant, cologne, or laundry detergent. Especially seeing as she's sniffing everything you touch and wouldn't lay on your sweats. It's hard for our pets to tell us what they want or are thinking, but they do give us clues if we pay attention to them.

Knowing your cat and her habits as well as you do made it very easy to see there is definitely something wrong. Good luck. I hope she feels better soon.

We have a 13 yr. old cat too. She has lately changed her behavior and at her check-up for shots, etc... I asked the vet, that same question. He said, it could be many things but she seems healthy and shows no signs of illness. He asked about her eating habits and we told him they hadn't changed. He said he could run some test, but he simply thought it was part of the aging process. Apparently she's getting grumpy in her old age.

Hopefully your cat will get back to normal soon.

My first thought is old age is catching up with your cat. Just like people, pets sometimes get "cranky" and don't want to have much interaction with others as they age.

I recently had to put my 22 1/2 year old Siamese cat down. For the last couple of years she lived on the kitchen counter. The only time she came down off the counter was to use the litter box or if she came looking for a little love. When she was younger she was with my wife and I constantly, always wanting to be involved in the goings on at home. Over the years her interactions became less and less frequent.

Hope things work out for you and your kitty.

Vaccines can affect your pet in many ways. Including personality changes.

Many pets are over-vaccinated.

Especially if they are always indoors like a "house" cat and are never around or exposed to any other animals.

I really don't have any advice, I don't know cats but I really feel for you. I hope that it's just temporary and that it turns out ok.
Sometimes in dogs issues with the brain can cause behavior changes,tumors, etc.