Check on the uni’s sites for room and board costs, some schools are cheaper (maybe 8-10K, some more) but you are going to need accommodation during vacations also. Again, full rides are not common at all. Full tuition still leaves you with living costs. You pay to live at a UK uni, you pay for food and board. You will not get a loan in the USA. You will be financially, persona non grata, you will have at best, a student visa, no credit and no job. No one will lend you money.
@Alfonsia Doesn’t full ride mean accommodation is covered too? If it isn’t i still think I can go because I think the rule with my parents is: we can pay as much as we would have to in the UK. So accommodation + food + books. It’s the tuition that’s the problem.
It all sounds so impossible 
Tvistz, saying “I just…can’t. I detest it. No one understands how much I hate it here” makes you sound as if you are not approaching this maturely. I understand the attraction of southern California (especially if, as seems likely, you have been there on holiday). But it is not your only option for choosing universities beyond the UK.
As an EU citizen you have the whole EU to choose from- and English options in more places than you might expect. Aside from Ireland (which has some great options, and obviously is English speaking), here are some Finance courses taught through English in countries from Sweden to Italy, from Spain to the Czech Republic- and many places in between:
Most of them for much less than it would cost you to stay in the UK.
Irl, California is not a realistic option for you financially. I am not unsympathetic- San Diego is a beautiful place, with great weather- but the sooner you see that (at least for undergrad) you need to look elsewhere the sooner you can start building that path.
@Tvistz What can your parents pay? At Alabama you could have your full tuition paid for. For a full ride look at the University of Kentucky. You said that they would pay for room and board and books. Why would Alabama be a problem then?
@gearmom, My parents can only pay for my food and accommodation and books. Alabama isn’t a problem but it might be hard to convince them to send me to a college so far away from family. It’s still a possibility obviously.
Could you also take part of your government-subsidized loan (UK) and use it in the US?
@MYOS1634 I think you can take a loan here and use it in the US but not a student loan, and if I get a personal loan it will be very very hard to pay off and definitely hard to get in the first place. My parents don’t really want to do that.
I did mean the study loan that is subsidized and that you only pay back when your salary hits £25,000. I know that some students do that (ie., borrow their government-subsidized loan to go study abroad.)
NO, the UK education loans system will not give her money to use in the USA. The only loans would be personal.
I think that option is for universities within the EU, MYOS1634.
Tvistz, you have so many great options within the EU- including some warm, beachy places. It’s not clear to me why (say) Alabama would be a better option for you than (say) Spain or Italy, which would be as good academically, as agreeable in living circumstances and vastly less expensive. As the courses are taught in English, your classmates would all be fluent English-speakers, so not a hard transition. Or, if you want all-English, Ireland would give you a great student experience and strong academics. Trinity College Dublin or Alabama?
@collegemom3717 Because put in the simplest terms: I want to study in the US. I’m not only looking for warm weather and good colleges. I’m looking for US colleges.
Well, good luck with that.
Apologies, Tvistz…I guess you have moved on from here:
"I’m looking for a college in Southern Cali that has a finance major for undergraduates and is no more than 30min-1 hour from the beach. That’s all!
“I’ve been looking at colleges and LMU seems really suited to me. It’s near the beach, in California, does the major I need, etc.”
“There are a lot of factors in my decision to go to the U.S., but the main one is just how much I dislike the UK”.
The hard reality is that for you to get the kind of aid that you need in the US, you will have to go to a much lower ranked school than you would qualify for academically.
You are clearly smart and hard working, and want to be someplace else. So, if you can’t get 100% of what you want, maybe you can get a lot of what you want. For example, you could go to Trinity College Dublin (very inexpensive for your family, out of the UK for you), and spend a year at the University of California or University of Southern California (school sanctioned and organised, so easier parental approval; tuition at EU rates, not US rates, so more affordable, and a year in California for you). More info here: https://www.tcd.ie/study/non-eu/study-abroad/from-trinity/college-exchanges/Partner%20Universities/
It’s not either-or. You can apply to a variety of schools, in English-speaking countries, in countries where you speak the language, universities in nice locales that teach in English… You can apply to Sciences Po and Bocconi and Insead… AND apply to US colleges.
Also, I’m not sure Honors College at UAlabama doesn’t beat Trinity College. It beats TCD on opportunities for research, for instance; even if the average UTD student is better academically than the average UA student, I imagine them to be roughly at the same level if we compare Honors College to UTD (top 10% to top 2% nationally). If you don’t like Greek Life and big football, prefer cool rain to humid mugginess, then UTD’s better.
In addition, look at exchanges like the one collegemom3717 mentioned: not your ideal situation, but still another alternative. I know the university of Bordeaux has such an exchange with the UCs (you need A’s to participate, but if you picked English for a major, I hope you’d get them :p).
Irish and Scottish universities tend to have a more flexible curriculum than other universities.
“There are many ways to skin a cat”, many roads to lead where you want. Don’t close any venue, try everything. 
agreeing with MYOS1634 overall, except…Dublin > Huntsville by a country mile
UAlabama is in Tuscaloosa. Way better than Hunstville. Not nicer than Dublin, for sure, though, but a nice college town.
oops- my bad! but yes…