(http://i.qkme.me/3p341o.jpg)
OR
(http://www.readysetfeast.com/wp-content/uploads/2012/05/punkd1.jpg)
I know how you feel. This has actually happened to me once, but in a different way. I was advertising for an RP out in Flourite Plains when I got a whisper from some random person, asking for an invite into my group. It went something like this...
Person: Can you send me an invite? I would like to join your RP.
Me: Okay -sends invite-
Me: Invite sent
Person:..... Can you send me an invite please?
Me: I did
Person:....... CAN I GET AN INVITE!!!!!?
Me: I already sent you one -sends another invite-
Person:.............CANNNN I GETT AN INVITE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!?
Me: I already sent you one twice.
Person: Forget this!!!!!! I wanted to join your RP but NEVERMIND!!!!!!!!!!!!!
That's pretty much how it went. I ended up reporting them since they started swearing at me via whisper. I'm sure they thought what they did was funny... until they couldn't log back into FH after a mod saw that report. :D
Best thing to do is block them if they keep bothering you, and take a few screenshots of their bad behavior and send it to a mod.