Business or pleasure. What kind of class do you want?

So here's something to think about. A student in my SPED class who is a teacher said something interesting that I don't think I agree with but I'm open to others opinion. She said that you don't want to be a students friends because that is the "kiss of death". Now I understand in particular ways you don't want to be a BFF with a student, but I happen to believe in the care/relationship that should be established between teacher and students and I think in many respects that means becoming friends of sorts. I feel that forgoing that part will make a untrusting business like environment that will do student nor teacher any good. What are your thoughts?

-Kelly