Okay so about my tricking my gf...?

At first it was just to ahve fun but when i made the fake myspace my intentions werent for her to really lie to me it was just to mess around. i just wanted to be funny ya know but then it got a lil bit mor eintense or should i say a lot a bit cause now she is denying me to this guy that is really me and shes telling him that im her step bro... and she doesnt know that im really the one she is talking to but now i dont know what to do becasue i didnt even mean for it to be this way.... Gahhhh what do i do?