She has flown off the deep end

This malaphor was found by Bob Ferrante as he was reading the Huffington Post.  It is a mash up of “gone off the deep end” and “fly off the handle”, both meaning to get extremely angry or crazy.  The blended idiom comes from a discussion about the actress Amanda Bynes:

“In case we needed any further proof that Amanda Bynes has flown off the deep end, here’s her latest outlandish Twitter remark…”

http://www.huffingtonpost.com/2013/03/28/amanda-bynes-twitter_n_2970924.html