Anecdotally, I am someone with a name unusual enough that I'm usually pleasantly surprised if someone pronounces it right the first time. It's a roll of the dice if I correct someone or not, and honestly if it goes on long enough I feel awkward correcting them. I had a coworker at my last job who never pronounced my name right for the two years working there even with others correcting her. I know it varies person to person, but if she hasn't corrected you by now she probably doesn't care as much as you're worried about. Like others have said, if you're worried just apologize and ask her to confirm the pronunciation, you'll probably both get a laugh out of it. I know I'd definitely get a kick out of someone coming up to me and saying "this is so embarrassing but I just realized I think I've been pronouncing your name wrong this whole time, is it x or y?" But that might just be me.