I think I only see this going one way.

I'm gonna end up loosing the plot and screaming at her ''Leave me alone! I don't want to bum you or your brother!!''

Seriously though.. Sads, thanks for the advice I think i can use that to fuck this stupid crush off out of it but she is still hot and still a flirt and still fuckin wants the big man cock!! I AM happily married and would never cheat (ESPECIALLY UNDER THESE CIRCUMSTANCES) and I didn't ask for this situation I just need to figure out how to deter her because I'm worried I'm being to polite for my own good.

Okay my question is this, how the fuck do you deter a hormonal teenager while a) remaining professional and b) preserving your own reputation?