Everybody I know loves being at Bristol, it's such a nice uni. I only know two people who have dropped out. One of them didn't like being away from her boyfriend, so she transferred into second year at Reading so she could live at home. But she seriously made no effort to make friends. The other realised she hated her course, and Bristol didn't offer any other courses she really wanted to do, so she moved to Southampton.
Don't worry about going home, because there are regular direct trains from Bristol to Southampton which aren't very expensive if you book them a week in advance, so it's easy enough to get home when you want to.