Well we can't tell you if you need to be upset. Yeah I think you have a valid reason to be upset, but if this doesn't bother you, then so be it.

But since you made this thread I'm guessing it's bothering you at least a little bit. If it bothers you a lot you might consider removing her as a friend on facebook. If you think de-friending her would cause too much drama, change your privacy settings to limit what she can see (such as likes). Some of the privacy settings are really subtle and she shouldn't notice unless she's studying your page.