Completely confused and overwhelmed

I wasn't exactly sure which category this would be under. This is going to be pretty long so please bear with me. I dont really have anyone to talk to and I just need to get this out. I'm an 18 year old female and in about a month I'm going to be graduating high school and moving across the country. See, my family is from the west coast but we moved to the east coast almost 9 years ago for job reasons. My family has decided they are moving back west literally the day after I graduate. I committed to a state university on the west coast for a variety of reasons but mostly because the distance from family will make things "easy." I've started to realize nothing about this is easy and its really freaking me out. I never had a dream school or that "ah ha!" Moment when I realize this where I want to go or this is what I want to major in. Basically I'm completely indifferent about the school I have chosen and while it is a nice school, I'm terrified I'm going to regret my decision. I'm also starting to realize I'm going to be without a support system. I'm not particularly close with any of my family except for my dad. They are definitely more of a source of stress and anxiety than anything; however they are also the source of tuition $. I have a solid group of friends on the east coast and I can't imagine being 2,000 miles away from the only people that care about me and who I'm comfortable with. I have an amazing, tight knit group of friends who have helped me deal with my family and so much more. They are all staying relatively local after graduation. Half of my friend group is in the grade below me, including my close guy-friend of a couple years who has recently become my boyfriend. I don't know how the distance is going to impact these relationships and I'm scared of being alone/forgotten. I know people say you drift from hs friends after graduation, but there are three specific people who I love and want to have in my life forever, and I feel like I'm putting that at risk by making this move. I know I'm not the greatest at describing the situation but I'm literally starting to shut down because of the stress and I want to enjoy my last month of highschool. So thank you so much to everyone who is still reading. To sum it up, i'm leaving something great for a life I'm not sure that I want. I'm afraid that I've made decisions for the wrong reasons. I'm putting relationships that I value at risk in order to be in the easiest location and I am so incredibly unsure about my future it actually makes me sick. I'm not sure what exactly I'm asking for.. Advice, words of wisdom, something to help me figure this out or put my mind at ease.

(Superb advice, RO, welcome aboard! :-))