What does it mean when a taken girl flirts with you?

I've known this super nice girl for a while now but has a boyfriend. She has always been real nice since the beginning holding cool conversations whenever. But sometimes she doesn't talk to me almost like she's shy or something. I don't talk back cuz well...I don't want to push it if she doesn't feel like speaking. She flirts with me from time to time and it confuses me. She already is in a relationship but yet she gives a vibe of "i am interested in you". I draw, and whenever people see my drawings she always says I'm such a good drawer and how I'm super talented. I don't even have to say anything lol.

Since I know she has a boyfriend, I hold off from flirting myself because I think it's a little wrong so I try to ignore it from her too. One time she even tried to put her hand on mine pretending like if she wasn't aware of it but I saw it inch closer. I let it happen cuz I wanted to see how far she'd get. It baffles me really!

So girls what does this even mean? Is she not taking her relationship seriously or having complications, or am I just misreading the whole situation? :\
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+1 y
Hey thank you everyone for the responses. In these kinds of situation there's not much a guy can do but all then different opinions a can change perspective. Again, thanks.
What does it mean when a taken girl flirts with you?
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