Honestly, I have no idea.
The best available research indicates that it's impossible: she is hit on so consistently and constantly that, here at the bar, she notices flirtation aimed her way the way most of us notice gnats in summertime: just a thing that happens, of no real significance.
Not hitting on her offers you no advantage, either. Like most people with good self-esteem, she seeks the click of instant mutual attraction. Your resolute attempt to draw her attention by not drawing her attention is thus, by definition, doomed to fail.
But take heart: though she does not love you and, as best as science can tell, never will, it is very much like she loves you. For just watch her. (No, not like that. In action, I mean. Don't stare. Yes, she has very fetching cleavage, and she's not wearing that blouse by accident, but that's not what I mean.) Watch the careful-yet-assured way she holds the jigger while she measures the gin and then the vermouth as she prepares your martini. Watch how delicately the mixing spoon swirls within her fingers. Watch how she spears the olives on the toothpick just so, dead through the middle of each.
No, this isn't love. But it is done with the care of love. Enjoy your martini and accept that this is enough.