I need help with a Jekyll-and-Hyde cat I have. She is very aggressive towards 2 other cats in our house.?

She is a small adult cat, over 2 years old. I had her spayed last year, hoping it would defuse her aggressive streak. Just today, her attitude toward the other 2 cats she HATES is worse. She had ALL the cats in the house (4 of them) in a spitting, hissing uproar, all of them chasing each other and fighting and growling. I should add, it seldom happens, that ALL of them start fighting. All the cats at our house stay inside. This cat, Domino, who can be very sweet when the other cats she hates are not within sight of her, even attacked ME when I was trying to stop the fighting. I'm really beginning to wonder if there is something wrong with her mentally. I cannot take her to the vet to be checked, as I don't have the funds for that at present. I'm tempted to just put her outside and leave her outside, but she's never been outside before since I found her as a little kitten. Does anyone have any ideas?