I have two cats, one female (small – 7 lbs) and one male (big – 18lbs). I adopted them together from a shelter (they shared living quarters at the shelter), and I’ve had them now for about 10 1/2 years. The three of us live together in my one-bedroom apartment and they are indoor-only cats. 95% of the time they are good friends and will sleep/cuddle together, and groom each other, eat together, etc.; occasionally they tussle but they’ve NEVER ever really hurt each other or drawn blood. I should note that the initial aggressor (when play fighting) has always been, surprising, the diminutive little female; she definitely ‘wears the pants’ and is the more dominant one personality-behavior-wise, and also asserts herself more in terms of being close to me/having my attention (the one exception: in situations of play with chase/catch toys, where the male cat is clearly more aggressive and a much more serious ‘hunter.’)

Well, I left the house for about an two hours yesterday afternoon and returned to find cat hair (mostly hers) and cat pee (his, I believe) all over the place; the male (black) cat still had a mouthful of the female’s (white) fur, and she was cowering under a chair and they were both low growling & hissing at each other and would hiss & growl at me if I tried to get near either of them. In the 10 1/2 years I’ve had them, neither of them has EVER hissed or growled at, or been aggressive toward me – and neither of them has ever done any ‘business’ outside of their (shared) litterbox. At one point they started actively fighting again and I thought for sure they were going to kill each other it was so loud and aggressive and violent. (My one bedroom apartment isn’t very big for a big, violent fight like that!) The little female finally ended up cowering under the bed and I finally managed to trap the hissing & growling male — but not before he’d peed all over again; I put him in a carrier with a blanket over it just to separate them and try to calm them down. The female continued to hiss & growl at me every time I attempted to get her out from under the bed.

I should note that she had been at the vet just the day before, for an ear infection (she gets them chronically, and has ever since I’ve had her) + possible UTI/bladder infection (a first). But when I’d come home from work she seemed to be doing/feeling fine, and I’d given her a dose of her ear medication before going out again to do a few errands. But all hell had broken loose during the short time I was out doing errands…

I was finally able to pull the female out from under the bed after several hours, although she continued to low-growl at me the entire time. She has a small wound on her front paw (which I did my best to clean) –so the male cat clearly hurt her during the fighting. By then I had taken the male cat out of the carrier and sequestered him in the bathroom, with his own litterbox, food, water, etc. He seems totally fine — uninjured, no longer hissing or growling at ME. I made a makeshift second litterbox for the female cat, and she has the run of the rest of the apartment. And while she eventually ate (heartily) and eventually slept on the bed with me (as per usual), she is still vigilant about the bathroom door and the whereabouts of the male cat. She seems totally scared of him now, whereas before –if anything– he was scared of (or deferential toward) her.

I’m terrified to let him out and let them near each other again; this whole experience has been so traumatic — for all of us!! What’s worse, I will be going away this weekend for two nights/3 days on a work-related trip… Normally I would leave them on their own, together, which is something I’ve done many times over the years without issue –with the exception of some occasional ‘anxiety barfing- since they’ve always gotten along well and are both ‘self-feeders’ or grazers.

I’m taking the female cat back to the vet today to have her wound treated. And I plan to buy one of those plug-in pheromone diffusers as well. But how, exactly, should I attempt to re-introduce the two cats to each other…?? Or should I even try?? And what if this aggressive behavior between them persists? I can’t very well keep one cat cooped up in a tiny bathroom 24/7 — and my apartment just isn’t designed/big enough to create other separate living spaces for them. Is it possible I might have to surrender one of them to another home or, worse, a shelter…?

I volunteer –working with cats– at my local SPCA, which is a no-kill shelter where the animals receive wonderful care & treatment; but still, I never imagined I would have to return one of my own cats to a shelter!

Help!! Are there any other comments or suggestions for my situation? I would be so grateful for any advice, suggestions, etc. Thank you.