Complicated female, outdoor cat territory fights

Question
I have had my cat for three years now, and she has always been the most
loving, calm and friendly cat. We moved into a new house about 5 months
ago and apparently has been having continuous issues with the female cat
that already lives here. My situation is rather complicated though, because I
live with other people, in a house that is very outdoor friendly. We have a
huge backyard and it is really difficult to keep my cat indoors. She has been
chasing the other cat, who lives outdoors only, and it is starting to create
tensions with my other housemates. (Of course, they didn't tell me about it
until recently) and I NEVER see my cat doing it. She always acts like a princess
around me.

I have tried to keep the cats separated, but my cat LOVES the outdoors and
goes crazy when she is locked inside. I don't know what to do to train her
(especially 5 months in) and keep her from fighting with the other cat. I don't
want to have to give her up, and i don't want to move. Help!!

Answer
Lewis,

You don't mention whether the females are spayed. If not, they need to be done. That corrects a lot of behavior problems.

You have a territory issue. Is your cat a Calico? She sounds like it! When you have new cats meeting, you need to go through a correct introduction process which can take up to a month or more.
The most important thing about introductions is to go SLOWLY! Do not try to rush it or force them or you WILL end up with behavior problems. I am including some excellent links to articles on how to do the introductions properly. They may not all pertain to your situation but they should be helpful as a guide.
(copy and paste, or type the whole links into your address bar)

http://www.messybeast.com/first-impressions.htm

http://www.littlebigcat.com/index.php?action=library&act=show&item=cattocatintro...

Here is a link to an article about a bully cat:
(Copy and paste, or type, the whole link into the address bar)
http://www.catfactfiles.com/how-can-i-stop-my-cat-bullying-another-cat/

Once they can be together calmly feed both cats yummy cat treats (like tuna or pieces of raw steak) TOGETHER. That is so the cats will associate each other with something pleasant.

Try to get both cats held by you and/or someone else and pet both together so your cat can see that the outdoor cat is friend and not foe, and belongs there.

Also getting a pet laser light (at PetSmart, etc.) is great for interaction between the two cats. You can do it outside at night with the outdoor cat. They both can chase the 'little red bug' on the floor, ceilings, and walls, and they tend to forget about the other cat as they focus on the 'bug' which helps them get used to each other.

Maybe you can work on making the outdoor cat used to coming inside. Then you can put one out and keep one in, then vise-versa so both cats can enjoy the outdoors until they can get along.

I hope this helps.

Tabbi