HIGHSCHOOL PROBLEM !?

[Diego]

Okay this is my highschool Issue

Theres this girl in my 2nd period class
Shes cute and everthing
I talk to her during and after class, also i walk her to class sometimes
One time i asked her if she had a boyfriend she kinda smiled down and looked away then she replied saying "no."

Couple days later i check her facebook profile
And one of her statuses it said
"im glad im still with him nobody can tear us apart 7.15.2012<3"
And shit like that.

It says she single but she has no picture of the guy or has mentioned his name,
So she has a boyfriend.

But since the first day of school she has been looking at me during class , like quick glances and shit like that

But i still talk to her and flirt with her , but she doesnt do anything , she just goes for it and i can tell she likes me .

So my question is whatshould i do

Should i countinue flirting with her

or should i stop ?