I don't know what to do...... It's different.?

So like I said before I love my best friend. But she's a girl and I'm a girl (I'm BI). She hints off often. But I can't tell if she likes me or she is being very friendly. But at the same time I'd like to come out to her and her only, but everybody on Y!answers says " make sure she knows you don't like her." But I do and I want to be with her bad. I don't know how she would respond to this. I don't know if it would completely tarnish the relationship. Or would it take it to new heights . Please help my situation.