Burger King Bathroom

I stupidly hooked up with my manager at my part-time job at Burger King. In the Burger King bathroom. I haven't worked since. I'm so anxious about how I will be treated at work now, and I have a boyfriend of almost a year, so do I tell him? I honestly don't think I have enough courage to tell him that I gave in, because I have previously told him how this dude has constantly been trying to get at me at work, but ... I just needed to tell someone honestly