It really depends on the cat. I have some cats who hate EVERY other cat, yet I have a 9 month old kitten who has already been a foster "brother" to two litters of newborns I've cared for. He cleans them, cuddles them, and plays with them. But...he is the sweetest cat I've ever met. He likes everyone. He and his sister were fosters we decided to keep (DH fell in love with him and insisted on keeping them after accusing ME of being the crazy cat foster lady!), so he has been here since he was 4 weeks old. 4-week old blue-eyed Linus is my avatar.
When our 3 older cats bat at him or attack, he simply lies down or rolls on his back as if to say, "Ok, I wanna play, too! Oh, what, you don't like me??? Why? I'm a nice kitteh!" When we were at the vet a HUGE dog came charging up to his carrier, and before I could pull it away (I had two of them stacked up) the dog slobbered all over the front and Linus never moved or even cowered. He stuck his paw through the carrier to try to shake hands, He simply likes everyone and every critter.
However, you can't be sure your girl will be like that. In all my years of having hundreds of cats and kittens (almost all were fosters) I've only had 3 who were like Linus. I really wish he was female, because my last female "foster sister" was able to nurse the babies even though she'd never given birth. My vet said it was a simple physiological response to the kittens nursing on her, but after a week they actually got milk! Made my life so much easier, and the kittens were so much happier. That's SOOO not going to happen with Linus. At least I hope not!
The "traditional" method of introducing a new cat is to confine the "interloper" to a separate room for a week and gradually let them interact. Since the kitten is so young, I suggest keeping the kitten in a separate room or container for 24 hours, but LET YOUR CAT see the interloper arrive. She needs to know he's there or she won't want to investigate.
Bottom line, she will not like him, at first, unless she is a mutant, like Linus. But...since she is still a kitten herself, and was abused, she might like the newbie just fine. I would forego all logic and have someone else bring the kitten to your house, preferably someone she knows. Then, let the kitten out and see what happens. You definitely need to monitor interactions VERY closely, so that the kitten doesn't get hurt. Remember that hissing and tail-puffing is perfectly normal for your cat. This is, after all, HER HOUSE! and the kitten is an invader.
With any luck, in a week or two the two fur balls will be curled up sleeping together and bathing each other. Good luck!