Can a girl really just forget about someone she really cares about?

She really cares about? It's a long story, but I mean she is just forgetting about me. Things were so good, I mean great. But she's forgetting about me. She won't speak to me. I'm giving her space, but it's like I've just dropped off of the face of the earth. Heck, this weekend we were supposed to go to a wedding together, and I didn't even get a de-invitation. She just won't talk to me. I am giving her plenty of space. I said hey on facebook the other day and she just won't talk. I mean I don't know what else to do..what we had was so real, but being headstrong can she relaly just forget about me? Because right now that's what she's doing. Will she come around eventually?