Work colleague

Hi. I work with a girl who I have recently developed extremely strong feelings for. We have known each other for about 18 months, but in the last couple we have grown closer as we've worked more together and now I have completely fallen for her. My issue is that I am technically her boss, I'm 6 years older than her and we work very closely together (often 6 or 7 hours a day 5 days a week together). At this moment I have no idea whether she feels in any way the same for me as I do for her and I am concerned that if I tell her how I feel, and ask her out, if she says no it will make our work lives unbearable, and so awkward that it will ruin any relationship that we already have. I would welcome any advice or thoughts.

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