I(F21) have so much anger for my autistic little sister (4yrs old)

So yah. One hell of a age gap right? I was 17 when my parents decided to have another kid. I was so angry and honestly still am because I don’t like children much less a noisy child living in our small 2 bedroom condo where me and my twin sister already share a room. Now add a baby? Me and my mom had this promise from the time I was younger that she would never have another kid and we both agreed two is enough and we are happy with the size of our family. She broke that promise so honestly, I never liked my sister from the start and lost respect for my parents as this was a golden promise that she promised to keep. Betrayal of the utmost was felt in my heart. My mom has always been tired from working and taking care of the house and my dad, me and my twin were finally about to leave the house for college and just life stuff so it would have been a peaceful life now for my parents. But noooo she just had pregnant, decide to keep it cause of empty nest bullshit keep in mind WE HADNT EVEN LEFT FOR COLLEGE YET I WAS STILL A JUNIOR IN HIGH SCHOOL, and has to raise another kid to 18 when she was already in her early 40’s and my dad early 50’s. Great.

So when baby hit around 1 and a half we noticed some off things. She wasn’t talking or showing signs of it. She wouldn’t respond to her own name, her fine motor skills were close to none. So my mom goes to the doctor and yup, autism. As she grows it seems to be getting worse and worse. She climbs everywhere, knocks everything down, takes things out of cabinets, jumps from high places, runs into our rooms and messes them up. She unplugs outlets. She constantly is banging utensils on things(my laptop has a ton of dents from this habit). Our house is constantly a mess. Almost everything is broken or waiting to be broken. We shoved a trampoline into my living room to give her space. My once beautiful living room is now a shadow of what it once was. The dining room no longer exist we took away the chairs and table because of her climbing. We no longer have a computer desk area because she broke our house computer and climbed on the desk. I’m so fucking depressed as to what my childhood home has become. She’s still not talking and these behaviors lead me to believe she’s a level 3. It would help if some of you guys could help me confirm my theory that she is because honestly I’m losing hope. I’m constantly scared that my parents are gonna die and I’m gonna have to be left to take care of her for the rest of my life when this isn’t what I wanted. I never wanted a little sibling, not one 17 years apart in age at least. My mother is depressed because of the autism and feeling hopeless about the situation. I just can’t do this. I constantly wanna escape back to my college apartment but I don’t want to leave my poor mother alone. I just wish this problem never existed. I constantly wish for someone to make a time machine so I can stop my sister from being born. I love her, but it feels more like a familial obligation than true love.

I don’t know guys please help me or give me advice, does this get better? How bad is it that she’s 4 with these destructive habits and no speech? Anyone have similar experiences?