I cannot stand my "internship" anymore

OK I am at my breaking point today....I started to work at this internship 2 years ago in November. I had just changed majors from Comp Sci to Poli Sci and was desperate to get any experience. I had a previous internship and was still vastly under qualified, but somehow I was able to pull off some connections and aced the interview and got the job. I started with another intern, lets call her Alice, we both went to the same undergrad were excited to start a job at a well known law firm. Well flash forward about 6 months in both Alice & I were throughly done with the Associate attorney we mainly worked with, she was a micro manager and somehow were now drafting motions, certs, CIS's, etc. etc. the work was hard but we got to go to Court, mediation, speak with clients and much more so it was cool. We would often come in at 8 am or leave as late as 7pm.

CONTEXT I started at $17 an hour. My one year anniversary came and went that year and I didn't get a raise until about 5 months later. Again, I was really just loving the experience and they eventually bumped me up to $18 an hour. Yay I was happy..so I thought. The associate attorney quit shortly afterwards to work at another firm, it was bittersweet for both Alice & I because she was our first real boss in the legal field. We ended things on a high note and still keep in touch. We continued to work at the firm with the senior partner attorney, who at this point was supposed retire 4 years ago. In the beginning things were rough because the associate left in an abrupt way as they were supposed to take over our department. We got over this initial 2.5 - 3 month period and things settled. Alice & I started to get our work done and would do our best, we made mistakes at times because we are/were in undergrad and learned from them but everyone was happy. Until about 4-5 months ago, Alice left the firm because she graduated from undergrad and was going to law school, yay for her...she rocks and is a hard worker and she is doing great at law school.

After she left I also had to take about 1.5 months off to study for the LSAT and I've been back for a little over a month now. Now, it's also important for more context....because Alice left and our firm expanded to another two attorneys in our department they hired two more interns, Rebecca (a 3L in law school) probably the rudest person I have ever had to work with and gets smart with me in every other conversation. I've come to the realization that she is not Alice, she is not nice, and I don't need to be any nicer with her than just being professional. They also hired James, who is about 2 months into the job, he took some time off before going to law school and he is very nice & a great coworker. We also have a legal assistant named Lily who has been with the firm since she graduated high school and is just an amazing professional and an even better person, she's like my work mom and we are constantly working on things together.

There is another legal assistant named lydia who has been with the firm forever, she is work mom number two and gives us all interns advise guidance, helps us with handwriting we can't understand, and somehow has more social media than me.

So why did I say all of this and why am I over this internships, namely these reasons:

1. The senior partner has started to make my job a living hell. He waits till the last minute to get things filed, he doesn't even touch a computer so thinks things happen in the snap of a finger, and he starts emailing us at 5am with titles "ASAPPPPPP THIS IS NEEDS TO GET OUT NOOOWWWWWW" and then proceeds to leave at 1pm bc his dog has been home along alllllll day and the walker left him two hours ago. Listen, I get it...this guy has been in the industry for 40+ years and is a hell of an attorney. He needs to retire.
2. Rebecca is rude, jealous and just truly a bad person and an even worse employee. I'm not the boss but she will constantly leave things half done & then leave at 2pm bc she has a "headache", will comment on the fact I am allowed to park my car in our lot and not in the garage (bc of my medical conditions), that I talk to Lily & Lydia out of work (they text me and lw we talk bc we rant about our work and stuff lol), and will constantly give me snippy attitude when talking about cases or really anything.
3. I have asked for a raise TWICE...and I got ghosted by HR TWICE. I was told that I am "just an intern". I asked for $21 an hour because like me, Rebecca was hired @ $17 an hours but the second day on the job she asked for $25 and got it. I was told that I am just in undergrad and that number is not realistic. When I do the same work as Lydia & Lily, I will literally draft pleadings the attorneys sign it and then I file it. I could go on and on but I go way beyond my job description. They said that in November (last month) they would review everything and determine mt raise request. I accidently nearly walked in on a meeting with the attorneys and HR speaking about me and the only thing I caught was "Welllll he just came back from studying from the LSAT so he shouldn't get that". Which led me to not get a raise last month.

So....this leads me to literally hate my job. I have not gone to court and mediation in probably over 6 months. I am tied to my desk, I am not learning anything new, I am getting stressed sooo stressed trying to meet deadlines because we waited till the day of while the partner goes home to his dog, I will leave well past 5 pm all while being a full time student finishing my last semester in undergrad. I cannot see myself working three day a week here for the next 8-9 months before going to law school. I truly don't know what to do, for $18 an hour I could quit and work and retail and I won't be so stressed and burnt out right before three very hard years in law school.

Tbh, this feels so good to get out bc my family doesn't really understand and wants me to stay for the experience. I am not editing this and letting it be as raw as it is. So, if you have questions drop them down below and I will respond.