Aren't all Muslims Mentally Ill?

Channel 4 presenter Fatima Manji - Does she believe that the Koran is the direct revelation of God? If so, what does that say about her? 

By "Muslim" here, I mean someone who has freely made an informed choice to accept the teachings of Islam - perhaps someone like Fatima Manji, above. Because Islam is a totalitarian ideology that thrives on ignorance, intimidation and fear, that condition probably applies only to a minority of Muslims. The rest are more or less victims.

Many Muslims are mentally ill, or at least so we are told. Often we are told this after the Muslim in question has just shot, stabbed or slashed some random group of people, sometimes while shouting "Allahu Akbar!"

Skeptics complain that the "mental illness" attribution is often merely a strategy to deflect attention from the real problems - a preoccupation with death and violence, among other things - with the Muslim religion. I agree, of course, but here I would like to look at things from another angle. Let's take the mental illness claim seriously.

Consider:   

You read, perhaps in translation, a 1400-year-old book, originally written in classical Arabic, that claims to be God's ultimate and eternal revelation. It was supposedly dictated by God (through the mediation of an angel) but contains all sorts of odd mistakes, arrogant boasts and prominent "abrogations" and corrections, many of which are to the obvious benefit of the man whom God supposedly dictated the book to.

That man was a caravan raider.

One of the verses in God's ultimate and eternal revelation informs the caravan raider's wives that they should stop sniping and snipping at their husband for having sex with slave girls. He can have sex with whomever he wants. God later says that if his wives have a problem with that, it would be best if their husband divorced them. 

In a number of places in the book it is explained that if you kill "unbelievers" - people who reject the claim that the book was dictated by God - and you die in the process, you will  be instantly transported to heaven where, if you are a man, you will be able to have sex with 72 virgins forever, interspersed with sherbet breaks. The book is unclear about what you get if you're a woman, but elsewhere the caravan raider is on record as saying that there aren't many women in heaven anyway.

You affirm that this book is God's ultimate and eternal revelation, and thus confidently proclaim yourself to be a Muslim.

You wear your hijab with pride.

Aren't all Muslims mentally ill?