My older sister (I’m 17 and she’s 19) and I are taking a college course together (which I now realize was a terrible idea). Since the start of the class I’ve been doing all of our assignments purely because I want to avoid arguing with her. She can be really mean and hurtful when in an argument and I always end up crying (I’m also a female btw) so I basically let her push me around a lot. 

I eventually get fed up and tell her she couldn’t copy a homework assignment. She started yelling at me and refused to let me go to class until I gave it to her (she wouldn’t hand me the car keys). She says things along the lines of how I’m her sister and we should be helping each other out. She doesn’t have a job and she spends her time either at the gym or out with friends claiming she’s busy. She demands money from my parents (they both seem to have given up on her and just give her whatever they want so she doesn’t start yelling at them too... I sometimes think even my parents are afraid of her).

She called me an asshole and said a bunch of other personal things that she knows will hurt me. She tells me I’m useless and a terrible sister. 

I eventually manage to get the keys from her during the argument and I start walking towards the door. She then grabs my wrist (I have really small wrists) super tight and forces me to face her by also grabbing my face and turning it in her direction. Im pretty small so I hurt easily and at this point I was honestly scared of her. 

I ended up giving in and gave her the assignment.

We both get into the car and during the entire ride she is screaming at me. She’s one of those people who doesn’t let you get a word in when arguing so I sat there for a 10 minute car ride listening to her insult me. I was 25-ish minutes late to class that day because I couldn’t stop crying.

This all happened about a week ago.

My friends have all told me that I’m wrong and that it shouldn’t matter if she copies off of my work since we’re sisters. A lot of them said I overreacted and made a big deal out of nothing. I took their word for it and thought maybe they’re right but it still bothers me and I just want to know what you guys think. 