Im chatting with the girl i love in my class on gmail and her brother i admitted i love her and were still chatting about it and she said her boyfriend would kill her if she went out with me 
Meh. I'm best friends with the girl I 'love'.
It shouldn't be too awkward. Just don't make a big deal about it.
Also, she knows, if that makes a difference. Thought that might be obvious, but I figure it's worth putting in here.