I had a similar experience with a recruiter at Google ... only worse. Recruiters are the gatekeepers. In my case I was waiting for an answer on my interview at Google for 6 months ... just radio silence with no reply.
If you are lucky, maybe you have some friends at Facebook that can intervene on your behalf. If not, there's other companies.
I had friends at Google to help me get an answer. But I decided I never wanted to work for Google based on how callously they treated me during the interview process. It became clear to me that I was not a high priority person to them ... just a fungible commodity. This is true, but nobody likes to be shown the truth of their value like that.
I knew other people with other talents that were treated really well by Google. My skillset was not in that high demand ... or there were plenty of other candidates. But I felt like Google did not need to treat me like garbage.
After that I went and joined a startup. Quite happy now. We stole a few engineers from Google even :)
I always make sure we get back to our interview candidates as quickly as possible. I won't let us turn into a callous Google.