You are right. Quem Deus vult perdere, prius dementat. It's one of a number of pithy Latin phrases I have committed to memory.
Having said that, I would also contend that the incorrect paraphrase is correct. Pride will also destroy us. It is one of the "seven deadly sins," after all.
Don't ask me to name all seven. I would imagine I have been guilty of all of them at one time or another by now. The Lord is merciful indeed.