Search Results: response to flirting

Long story short. We work in a relaxed retail environment where banter is common between workers. A few months back when she was single but seeing someone. She started to become very flirtatious towards me, light touches, light punching, name calling, teasing, trying to get my attention, all of that sort of thing. I find her attractive so of course i would respond back and she seems to enjoy my responses as she always giggles and becomes childish. I think its obvious to her that i like her as other staff members have made joking comments about it to me. Recently she became official with the guy she was seeing. So respectfully i backed off of my flirting with her, well at the least the physical contact. But this has made her come to me more. she's been touching my arm, shoulder and face more than before. I can't help but respond even though i feel i shouldn't. From what I've heard and witnessed things are pretty rocky between this girl and her boyfriend. Should i talk to this girl about why she is carrying on with the flirting even though she has a boyfriend? Should i ask her if she's attracted to me? Or find out the situation with her boyfriend?