Yeah.. I hate it when people do that. My so-called "best friend" hasn't been such a great friend recently either.. She got a bf and now she like ONLY hangs out with him.. I haven't talked to her or seen her, from what it seems like, in ages.. *sighs* It's like she's disappeared off the face of the planet. When my other friends and I tried to plan something with her, she always bailed on the last minute.. Then she says she's been busy with work, but we all know she's also spent most of that time with her bf.
I'm sorry your friend did that to you.. you have every right to be mad if she did it intentionally.. maybe there's a chance it was a misunderstanding? I don't know... she still should have called you..