Don't listen to these omnipresent, self-serving women and their feminist or legalistic viewpoints, who presume to come to this forum and advise men. If I were you I would do everything I could to avoid exposing myself to the vagaries of modern divorce law and the dangers that it subjects men to. If she has serious mental difficulties, and a judge notices this in court and is angered by it, she could order a mental health determination which could ultimately lead to your wife being ruled incompetent and assigned a "guardian" (one of the judge's lawyer cronies--no doubt yet another woman). You could then be ordered to pay this lawyer, as well as her divorce lawyer, as well as having to pay your own divorce lawyer!
Before even considering divorce I would first buy some insurance, against being cleaned out, by protecting my assets. A good book to use as a basic guide to this is "Asset Protection Made E-Z", available at your library or from Amazon.com. At the same time I would try to get anything I could on her. You might be surprised at how quickly an off-hand comment, assuring her that you "would NEVER reveal (insert embarrassing or legally compromising facts(s) on her) to anyone", will assuage her hysterical determination to "get what I am entitled to". She will get the real, implicit message, and will not file on you--even if the explicit message is exactly the opposite!