You see, I'm with the OP on this one. I totally get it.
People that are saying 'oh she'll just be busy/hasn't seen the update/ just wants to chat to you in person about stuff' are very naive. When things like this happen, it's nearly always because someone is trying to prove a point/ have a subtle dig.
The fact that she may have 'hidden you from her newsfeed' isn't any better is it?! It's still not very nice that she's done that, especially if you're not too a prolific poster (I.e the 4 statuses a day 2, what you had for breakfast kind!)
The fact is, women DO use FB as a tool to be bitchy, to be excluding, to be conniving and to subtly shun people. I also do not like the people that are guaranteed to 'like' everything someone puts on FB, however, if you know something you've put on is (potentially) of particular interest to some one and you know they've seen it, it would probably sting after a while if they kept ignoring it, particularly when you know they're still running around liking and commenting on everyone else's stuff.
Someone started doing the exact same thing to me recently, I hid them from my newsfeed months ago now so I don't have to see what they post. I am soon going to put my statuses and posts so that they cannot see them too, I just have something coming up soon that I know will make them sick and I'd quite like to rub their face in it a bit before I say 'bye bye' the ultimate satisfaction would be for me to remove them as a friend entirely, however I do have to see them sometimes and can't be bothered with awkwardness so will leave it for now.
It's a sad world we live in, and a lot of us ARE too wrapped up in social media and let it rule our emotions too much, but you can't help how you feel and people being blotchy and nasty for no reason is never nice, even if it is just over social media.