Alright, my two cents, Seanathan: If telling her
does "destroy the friendship" for her, that is a very good sign not only that it wasn't meant to be, but also that the friendship wasn't really meant to be either; true friendship can survive a jolt like that. (And if it only destroys it for you because of shame, you need to just ignore the shame.)
I speak from experience, man. I told Lucky a long time ago how I felt about her, and she shot me down, but we're still close friends. What's more, she still knows that I still love her, but that never becomes an issue between us. In fact, I know EXACTLY what the answer would be if I brought it up again, because I've met her current boyfriend, but still it's not an issue between us....
he's totally clueless, but he has no need to know.
And remember, "I'm-a Luigi, number one!"