The impossibility of contacting Facebook

Two days ago, I received a facebook message from a friend that ran:

Hi Joan - someone is pretending to be you and sending our friend requests - just thought I'd better warn you. You probably should alert Facebook and get them removed.

Good lord.  How the devil did it happen?  Worse still, it triggered a small tidal wave of comments from other friends who had had the same experience.  They hadn't hit the link, so no one knows who the imposter is.  I can't find any other Joan Druett on Facebook, and the strange friend requests are not on my activity log.

So the problem, in my honest opinion, is Facebook's, not mine.  But contacting them to alert them to the problem is absolutely, positively impossible.  All I get a a flood of menus.  I did my best by changing passwords, and stopping any activity from foreign browser, so what else can I do?

Cancel my Facebook account?  That, from past experience when I had a strange shadow account, is not nearly as easy as it sounds.  If only Facebook was like other sites and other engines, and had a "contact us by email" function, it would help.  But no, the geeks behind the Facebook computers don't like real contact with the outside world.