What Does It Mean If The Hr Manager Just Stops Talking To You After Final Interviews?

I have been interviewing over the phone with a company for about 4 weeks now. I have had phone conversations with the Acct. Director, Supervisor and the VP of Acct Services.I have a friend that works there and said that everyone liked me. Last week (weds) I had my final interview before I was supposed to go to the company. However since then the HR manager that I have been dealing with has just disappeared, she will not return my call or email. This is for a major company so I am trying to give it two weeks before I really start to think that it is a no go. Has anyone experienced this, or have an idea of what might be going on. I haven’t received a letter, email or phone call saying that I didn’t get the job but at the same time I haven’t heard anything either. Any help on this would be appreciated *** I really want this job and am really trying to stay positive about it.