My fiances cat hates me and I have no idea why

Question
Hello! My fiance and I have been living in our apartment for about 4 months and recently (just before Christmas) adopted 2 cats from the local ASPCA. The first was a 6 month old gray short hair and the other is a 2 year old short hair. The younger one was skittish and hid all the time. Then one night it attacked me for no reason in the bathroom and caused some pretty painful bite wounds on my hand and sent me to the ER twice. The next day we took her back to the ASPCA and we kept the older cat, as she had done nothing to us and she actually was warming up to us.

 However, things have since changed. I have never stepped on her, or yelled at her, however she avoids me like the plague. She also has started hissing and growling at me. She always stays under our bed, and when my fiance is home she is affectionate to her but will retreat under the bed and leave if I even come in the room or she hears me. At night she will sleep next to my fiance Veronica, and all seems well. Until I reach to pet her then she puts her ears back and growls, then jumps off the bed.

  When Veronica is around I have also noticed something, she never growls at me or hisses when Veronica is around. When it is just the cat and I, and she sees me she will hiss and growl, and on two occasions attack me. She is even growling at me now, and she is under the bed, me on top, and she cannot even see me. In addition, the cat will never go into the living room anymore. My thoughts are something out there spooked her or scared her. She used to love going into the living room and laying with us while we watched a movie. Now she will not go out there, even if Veronica gets her, and puts her on the couch she runs back to the bedroom and goes under the bed.

 The only negative incident I can think of was when the cat was chewing on a USB cable for my PS3 I picked her up sort of  laughing at her chewing it. When I did she tried to bite me while growling and I tossed her, (not a throw) just a toss about 2 feet away from me to get her away from me (as I had just went through the other cat attack resulting in trips to the hospital) I did so in defense, because I was nervous about being bitten again. After that, she acted normal again and laid with us, and was normal cat again. Her recent attacks have been more aggressive, even to the point of clawing my hands and biting at my sweatshirts. A few weeks ago she also hissed and growled, charged at me while I sat on the floor trying to clean what I though was her urine, and when I moved out of her way, she missed me and hit the wall so hard, one of her eyes stayed not dilated for quite some time. Her other eye would dilate whilst the other would not. Her eye went back to normal a little while later, but her anger continues. I called the vet, and they said with it returning to normal there was little they could diagnose. When she hit the wall I freaked out and picked her up in her favorite blanket and took her to the bedroom and placed her on the bed. She then hissed and ran under it, where I left her alone since. I have stopped touching, talking or even looking at her, in fear of what might come next. My fiance loves this cat so much. Any ideas for what may be causing this and what could be done if anything? Please help! Thank you so much in advance.

Answer
Hello Matt,

I'm just going to firstly pick out some things that stood out to me and try and explain how she enterpreted certain things you have unwittingly done. Unfortunately you may have been unkowingly reinforcing her behaviour towards you. In a nutshell she is simply scared of you.

1. She is growling at you now because although she cannot see you, she can still smell you and she associates your scent with fear and an association of an unpleasant experience.
2. When you picked her up when she was chewing on the USB cable, firstly you may have startled her if she did'nt see you coming, secondly, laughing means showing your teeth which can look very threatening to a cat, thirdly, you (understandably) threw her a little, which she would'nt have liked, lastly, there may have been some kind of current, like an electric shock you get when touching someone sometimes, that passed between you and her which would have been unpleasant.
3.A few weeks ago when she hissed, growled and ran at you, it was because you where on the floor, probably on your hands and knees, maybe staring at her intermitently to keep an eye on her. This is all threatening and aggressive physical behaviour to a cat, you basically would have looked to her like you were about to attack her, and she attacked first!

At some point in the past you have scared her, fact. And I'm certain that you will not have any idea what it was you did, probably because to you, it would'nt have seemed like anything at all. This could be something as simple as arriving home from work and throwing your bag on the floor, which may have startled and scared her. Or one night when you were asleep, she could have been on the bed and you could have, in your sleep, jolted suddenly, which may have frightened her and made her very wary and scared of you from then onwards. Most people who find their cat suddenly showing fear-related aggression (which is what your cat is suffering) towards them will have no idea what they did to cause it. If they do, it makes my job so much easier! because we can pin-point and work on desensitisation methods aimed specifically at that fear inducing stimulus first, giving us much better chances long term. What we need to do here is start your relationship again right from the beginning, using two modification techniques which are systematic desensitisation and then counter-conditioning methods.

I'll try and make this as short as I can. (This first step should be taken over the space of a
couple of weeks or so). Go into a room where she is, stand at the furthest point away from her, do not look at her or talk to her, just stand there ignoring her. Do this every day moving a little closer every time until you can sit on the floor near to her and she shows no response. If she starts getting aggressive then you must go back to the beginning position and start again. The point of this is to get desensitised to you, getting her to a point wherby you and she can sit together and she shows no response. Next step is to change that 'neutral' response into a 'positive' response. You simply do this by sitting next to her and dropping a treat on the floor, still not looking or talking to her. Carry on doing this then gently incorporate talking gently to her also. Then whenever you are around together just drop food treats on the floor for her. By doing this you are using counter-conditioning methods, you are changing her response to you from one of a 'neutral' response to a 'pleasant one'. The rest will naturally come.

All the time you are in the house and around her, do not be noisy, do not directly stare at her, approach her, or lower yourself to her ground level. And just as another pointer, animals tend to least like tall people, wearing hoods, dark glasses or hats, these all look threatening to them.

These methods are complex so please go online and do some further research on these two methods so you can be more prepared.

I hope this has helped you a little and got you started on a treatment plan to help both of you live more harmoniously.

Thank you

Kelly