I didn't get on with my flatmates in first year either. We were just a weird bunch of people to have in a flat together really, we didn't gel at all. I had a similar situation with one who fancied me (although nothing happened between us, it was really awkward after he asked me how I felt about him and then I met my boyfriend a week later). I didn't even talk to my flatmates if I saw them around campus after first year. My best friends at uni are a girl on my course (everyone else has graduated), and the people I'm living with now who I chose to live with and have met since the beginning of second year. Remember you're just thrown together with your flatmates and you haven't chosen to live with them - by the laws of probability, there are always going to be flats like yours. I wouldn't worry about it, concentrate on the friends you have on your course because it seems like you have a nice group there, and you'll be able to choose the people you live with after first year.