What if I'm not scared enough to ask?

I'm too afraid to ask my gf if she's into the same fetish I am and she's not, but I think she might be. I've never even asked anyone about this before. I'm afraid she'll be grossed out and she'll break up with me over something that's completely harmless. Is it even possible for her to be turned off by my kink if I never even ask her about it?