New cat bullying all the others

I'm hoping to get some advice about my situation. We've had three cats for years now, and while they don't really like each other, they get along just fine. A few weeks ago, a stray cat showed up at our back door. We fed her and took her to the vet to get checked out. Her blood work was fine, so we brought her into the house and separated her from the other cats. She was also pregnant so when we had her spayed they aborted the kittens. Since she was spayed, she's been awful to our other cats! Before that, they were starting to get used to each other, but now she's really aggressive and possessive of us. She wants to cuddle, constantly and follows us around the house, which is fine, but she'll growl at the others if they try to get close. She's very sweet with humans, but I'm thinking we are going to need to find a home for her if she doesn't shape up! Our cats are our babies and I hate to see them so stressed out. I'm just wondering if this is a hormonal thing or if this is her personality and we need to find her a home without other cats. Thanks for any insight!

Hi and welcome to TCS! Hmm, I'm not sure if the spaying is responsible for her behavior. It doesn't sound like she was in the house long before the spaying? Did you do slow formal introductions? Have you tried a Feliway pheromone diffuser?

If you've tried everything and her behavior is the same, it may be best to rehome her to a single cat home if possible. She sounds really affectionate so maybe that won't be too difficult.

Oh, thanks! Yeah, she was in the house of couple of weeks before we introduced them (through a closed door and all that) and then had her spayed. I was just hoping it might be hormonal, because she really is a sweetheart. Our other cats were all adopted at separate times and did well with introductions, so I was hoping this one would go the same way. Sadly, I think you're right. We will have to find her a cat-free home.

It could be hormonal. It might take a few more weeks for her to settle down? I would try to give it a little more time, maybe with a Feliway diffuser for a few more weeks?

It's just so stressful for the other cats, and the new one hates being sequestered upstairs. I did try the Feliway spray, maybe we need the diffuser instead? Thanks for brainstorming for me!

I have no experience with this, but is it possible she senses the loss of pregnancy and that's why she's acting like this? Maybe over time she will adjust and settle into your home, but in the meantime is it possible to keep her more isolated from the other cats?

Yes, we  decided it would be best to put her back in the "cat isolation room" for now, but she gets so distressed if she knows we're downstairs, crying and scratching at the door. I don't know anything about pregnant cats, but I was thinking it would at least be possible for her to be a little strange after losing babies and lady parts. I have never seen a cat so needy for human attention. She is always on top of or right next to one of us.

I've never had a cat act like that after being spayed or neutered, but perhaps she feels the loss of the pregnancy?
 

I hope it works out and you can keep her in your home. Maybe this is silly but could you get her a few small stuffed animals? Or if you really wanted to be ambitious you could foster a litter of kittens from the local shelter. Maybe she would take to nurtering them for awhile. I know kitten season is starting, so shelters are going to be full with them.

In any case good luck with her, hopefully in time she will be able to settle in.

I have never had to rehome a cat due to behavioral issues; it is just not an option for me, as I believe adoption is forever, unconditionally.  Hopefully you will give her more time and consider some of the other posters' suggestions, particularly Agent Spooky's on that last post.  Our Sammi, a neutered Maine Coon who joined us at age 14 after being an "only cat" all his life, is still strongly territorial after 3+ years with us, but he has slowly adjusted to being part of a multicat family and now only occasionally "acts out".  He has his own room with all comforts and conveniences in case he needs a "time out", but he very rarely does any more.  The first year was rocky, but there was never any intention of relinquishing him.  Once adopted, a cat is FAMILY and family is forever.