I am currently in a situation where I do not know what to do, so I was hoping I could ask you for advice. Recently, my parents have become more controlling of me and my siblings lives than ever. We are all old (22,19, and 18), and their restrictions are holding us back from doing many things we need for the sake of our educations. They are afraid that if we are out past 7 PM something terribly bad will happen to us, and we’ll end up getting mugged or killed. I understand their fear, however when we go out at night we are not in dangerous parts of town, and we do not participate in any dangerous activities, since we are at work or at the university studying. Additionally, they keep trying to force religious standards on us, (for example, forcing my sister to wear the hijab in the way they like), and because of those force my sister has told me that she intends on taking off the hijab. When they talked to her about the hijab they cussed at her and told her they’d make her life hell, and it certainly did not help the situation. My question is, would it be alright to distance ourselves from them? What if we moved out against their will? Would that be haram?

Firstly you must understand the position of the parent in the eyes of Allah. And although their methods may be perceived as harsh by you and your siblings; from what you are saying they are acting in your best interests.
I can’t see any grounds for you wishing to leave the home, all you are doing is running away from one trial to a harsher one.
If your sister wishes to remove her hijab this is not due to your parents but more to lack of faith. Would you stab yourself because you hated your neighbour? This is pretty much the reasoning your sister is using to disobey Allah.
Allah is pleased when your parents are pleased and angered when they’re angered.
You need to listen to your parents and be a good and obedient child, because by what you have stated your parents are religious parents. Parenting is not an easy task, if you upset them you will suffer in life and then the hereafter.
Now, this is how you should deal with the situation, you should sit and talk to them respectfully and if they insist you must accept their wishes.
May Allah guide us all.