The Unthinkable: The wives of paedophiles who stand by their man.

It seems so clear. If your husband is exposed as a paedophile you simply pack your bags and leave. If you have kids together, you’d be out the door even faster.

You’re still in shock.

Your marriage is happy.

Was happy.

Now it’s over.

Except it’s not that clear a choice for many women who choose to stand by their husbands who have been convicted of some of the most depraved acts possible; those of child sexual abuse and child exploitation.

How are you meant to stay married to someone like that?

Just like this.

Sharon Henkel is one of many women who chose to remain with her husband after discovering she was married to a paedophile. Husband Bill was convicted in June of 2003 of accessing child pornography at work. He was sentenced to 15-months in prison but only served half of it.

Bill was just one of 700 paedophiles who had accessed a website containing 11,000 images and more than 1,000 videos of children being sexually abused. He says getting caught was the "best thing that ever happened to me" and admitted to his sexual attraction to young girls.

"Of course I was hurt and angry," wife Sharon told the Daily Mail. "We'd tried to deal with the problem together for years. I'd given him all the support I could muster. My comfort was that in every other way he was a good man and a good husband. I thought he'd keep fighting his urges. I never feared he'd become an offender. That trust was shattered."

Sharon says she was "sickened" when she learned what he had been doing. "I could have walked away then and left him to it, but within hours of him being found out, I could see his remorse was genuine."

This loyal wife believes in her husband's contrition. "I was disgusted, but it wasn't anything like the revulsion he felt for himself. His determination to seek help was stronger than ever. In the end, it wasn't such a hard decision for me to stick around and help him. I'd been in that role for years."

I can't help but think about one of the most disturbing cases of child sexual abuse in Australian history, that of Hey Dad! star Robert Hughes who was convicted of child sexual abuse. Sarah Monahan played daughter Jenny on the hit show and was six when she first got into the grips of Hughes.

Hughes was arrested in London on 9 August 2012, extradited to Australia and then in early April, 2014 was found guilty of sexually abusing young girls. He will serve a minimum of six years.

Wife Robyn Gardiner stood beside him and has paid a high price for her husband's crimes. A former agent to some of Australia's biggest stars such as Cate Blanchett, Anthony LaPaglia and Rose Byrne, she has since declared bankruptcy.

Sarah Monahan spoke to Mia Freedman on No Filter, discussing her long fight for justice against her abuser. Article continues after this video.

In the case of Hughes he was convicted of sexually abusing children, not just viewing images of child sexual abuse. Is the viewing of child sexual abuse less of a crime than actually performing the acts yourself?

Is that what some of these wives tell themselves?

Convicted paedophile Bill Henkel says that his "addiction" to viewing images of child sexual abuse was escalating at the time of his arrest.

"I did realise that the fantasies were getting stronger and I was becoming more and more obsessed. After a while, the material you're viewing doesn't give you the same buzz and you look for more extreme versions."

He says eventually even the most hardcore images didn't do it for him anymore.

"I recognised that my fantasies were going in a direction I didn't like and that I might not be able to control myself. So, yes, I think there was a danger that I might have tried to get access to a child, and I really didn't want to go there."

At the time of their Daily Mail interview in June 2007, Sharon Henkel and her husband Bill remained married and living together in their marital home. They had no computers so as to reduce the chance of Bill reoffending.

Seth Meyers Psy.D from Psychology Today believes women who choose to stay with husbands who are convicted paedophiles can't face the fact they've married a man who is capable of such behaviour.

He writes, "While the paedophile often feels little guilt, anxiety, or remorse about their own behavior, the wives feel significant anxiety but use denial and rationalisation to sweep their suspicions under the rug. They don't focus on the feelings of the victim because all their energy goes into feeling sorry for themselves because they made a mistake in choosing the wrong man to marry."

"The wives of paedophiles rarely admit to others that they knew or suspected what was going on, but these are their thoughts and fears in their most dark and private moments."

Australian police are working hard to continue exposing paedophile rings which use the dark web, peer-to-peer file sharing services and sophisticated technology in order to fulfill their depraved desires.

Late last year the the head of the NSW Homicide Squad, Detective Superintendent Michael Willing said in the course of their investigation into the disappearance of William Tyrrell they discovered there could be a paedophile ring operating on the mid-north coast of New South Wales where the three-year-old was last seen.

"We have information that involves the possibility that there is a paedophile ring that is operating and that may be connected to William’s disappearance," he told News.com.au. "We are vigorously pursuing that information, I can tell you that."

For every offender caught there is often a girlfriend, a fiance, a wife, a family.

For every wife who packs their bags, moves out and files for divorce, there is one who chooses to stand by her man and most people can't understand that at all.