Flirting

Girl with boyfriend acts flirty then asks me out, but claims as friends?

This girl i see at the bar all the time suddenly the other night has been extra friendly to me. Gets REALLY close to me and makes prolonged eye contact and smiling with me. Hanging around me, drinking, etc... This happened a few nights ago. Then, last night, she did the same thing again but started a conversation with me that lasted a while. Still laughing and giggling and smiling with prolonged eye contact that came off as flirty. She then found me on facebook (i don't know how she got my name) and added me and messaged me. She asked if I would like to go out one night. I asked her for what reason and asked her why she asked me that when she already has a boyfriend. Then tells me it's just a friend thing. Well, okay. That's fine. But why did she seem to be coming off as a huge flirt then add me on fb out of no where and word it in a way that seems like she is asking me out? Why do women do this strange stuff?
Girl with boyfriend acts flirty then asks me out, but claims as friends?
Post Opinion