I felt the exact same when I was studying English Literature at Edinburgh University. I did a semester, hated it (also hated my course) and dropped out at xmas time. Then I started Biomedical Science at Newcastle Uni. I'm now in my second year. Dropping out was the best thing I ever did. I went to uni to make friends and have fun as well as study and in Edinburgh my flatmates were not into going out much and I felt very isolated and lonely; probably the worst I've ever felt. Newcastle couldn't be more different, the night life is amazing and I have a group of close, like-minded friends who I am so glad I met, even if I had to go through dropping out first to end up in their year!
Try to join some societies and make friends that way, literally just impose yourself on new people and be as social as possible to try to make new friends. I know that can be super hard once you're stuck in a rut though and even feeling unsocial because you're so sad about how lonely you feel.
My advice is dropping out is not the worst thing in the world, it can end up being the best thing. However, it can depend what year you're in - as if you're in third for example might as well just stick it out.