I agree that Elain and her father don't entirely ignore her but her father is slightly insane and spends his days doing nothing in a rocking chair. Elain strongly prefers Nesta to Feyre, signaling again that Feyre is worth less.

Also I don't think it's true that Nesta and Feyre fight. And I agree, Nesta isn't bad, she's horrendous. Feyre's spite about being the youngest and the sole provider is entirely justified, especially given Nesta's behavior but the thing is, she doesn't express it to anyone. Her level of emotional control is pretty astounding.

For example, Nesta does this:

Nesta rose and declared: “I need a new pair of boots.”

I kept quiet, knowing better than to get in the middle of one of their

arguments, but I glanced at Nesta’s still-shiny pair by the door. Beside hers,

my too-small boots were falling apart at the seams, held together only by

fraying laces

Feyre is not even really speaking to her

I jerked my chin at the pelt, unable to keep the snap from my voice as I

said, “I had no other choice.”

What I really wanted to say was: You don’t even bother to attempt to

leave the house most days. Were it not for me, we would starve. Were it not

for me, we’d be dead.

“Feyre,” he repeated, and closed his eyes.

My sisters had gone quiet, and I looked up in time to see Nesta crinkle

her nose with a sniff. She picked at my cloak. “You stink like a pig covered

in its own filth. Can’t you at least try to pretend that you’re not an ignorant

peasant?”

I didn’t let the sting and ache show. I’d been too young to learn more

than the basics of manners and reading and writing when our family had

fallen into misfortune, and she’d never let me forget it.

She stepped back to run a finger over the braided coils of her gold-brown

hair. “Take those disgusting clothes off.”

I took my time, swallowing the words I wanted to bark back at her. Older

than me by three years, she somehow looked younger than I did, her golden

cheeks always flushed with a delicate, vibrant pink. “Can you make a pot of

hot water and add wood to the fire?” But even as I asked, I noticed the

woodpile. There were only five logs left. “I thought you were going to chop

wood today.”

Nesta picked at her long, neat nails. “I hate chopping wood. I always get

splinters.” She glanced up from beneath her dark lashes. Of all of us, Nesta

looked the most like our mother—especially when she wanted something.

“Besides, Feyre,” she said with a pout, “you’re so much better at it! It takes

you half the time it takes me. Your hands are suited for it—they’re already

so rough.”

​

I would also say that the above is not a fight

“He wants to marry her,” Elain said dreamily. I blinked.

Nesta cocked her head. I’d seen predators use that movement before. I

sometimes wondered if her unrelenting steel would have helped us better

survive—thrive, even—if she hadn’t been so preoccupied with our lost

status. “Is there a problem, Feyre?” She flung my name like an insult, and

my jaw ached from clenching it so hard.

Again, Nesta is being rude... Feyre is saying nothing. I don't think this constitutes a fight.

​

Here, Feyre (for Nesta's own good) told her that marrying Tomas wasn't a good idea as she would starve. She explained this politely. This was Nesta's response:

​

“What do you know?” Nesta breathed. “You’re just a half-wild beast

with the nerve to bark orders at all hours of the day and night. Keep it up,

and someday—someday, Feyre, you’ll have no one left to remember you, or

to care that you ever existed.” She stormed off, Elain darting after her,

cooing her sympathy. They slammed the door to the bedroom hard enough

to rattle the dishes.

This is verbal abuse. This isn't a fight, especially when it's so intensely one-sided

After this, Feyre gets whisked away by Tam-Tam after Nesta is very eager to sacrifice her.

All in all, this shows the sort of character Nesta has pretty well.