Look, man, in your initial post you said that she already had a
boyfriend. Let me quote from it:
this girl i like already got a bf.
So we gave suitable advice accordingly.
Now you tell us that you're not sure whether she has a bf. To be
brutally frank with you, you can't really expect others to help you
when you keep flip-flopping on your facts. Be perfectly straight
with us, and we'll do our best to help.
That said, just go and ask her once and for all whether or not
she's attached.
If she's not attached, then there's no issue. You can happily chase
her all you want, and we can close this thread for good.
If she is indeed attached, just follow the advice everyone has been
telling you: back off.