Marion Gibson was in Ontario for business in the fall of 2011 when she got a startling phone call from her partner of 27 years, John. He told her he was sick and on his way to the hospital by ambulance.

It was only when she got back home that she learned her husband was convinced she was trying to poison him. That was just one of many delusions he'd go on to experience that ended up throwing the Victoria family of five into a tailspin.

"Once I got home and could look in his face, I could see something was really wrong with him," Marion tells the Georgia Straight by phone. "He was having hallucinations where he could smell things. He said there was a bad acid smell in the house. He thought there was cyanide in the water supply and was drinking our emergency bottled water. He thought our light fixtures were bugged with listening devices. He was really scared."

19, 17, and 10. John was 45 when this all started, had built a successful career as a professional geoscientist, and was well-spoken, respected, and happily married.

But the man Marion started dating in high school began accusing her of cheating on him, sleeping with everyone from coworkers to acquaintances to mail carriers. He also suspected that she had been involved in murders and was linked to the Mafia.

This went on for months, with John in and out of the hospital and walk-in clinics. At one point, emergency-room staff sent him home with a prescription for Ativan, a mild sedative, for what they called a "psychotic break". The hospital referred him to his family physician for follow-up care. Finally, the couple began to get a sense of what was causing so much hell, what their doctor has since described as a schizophrenia-type mental illness.

"Before this, I didn't even know what the definition of delusion was," Marion says. "I don't think I would have been able to spell schizophrenia. It came as a huge shock."

John's doctor wasn't able to be more specific in his diagnosis, and the couple found it difficult to get high-level psychiatric care in Victoria. (One psychiatrist, upon hearing about John's suspicions about his wife's infidelity, told him to hire a private investigator and to catch her in the act.) But Marion says the couple is just relieved that the antipsychotic medication John takes is working and that he is now doing well.

The couple's experience with schizophrenia opened their eyes to the stigma that surrounds mental illness. To help eradicate the accompanying shame, Marion wrote a book about her husband's condition. The just-released Unfaithful Mind chronicles John's symptoms, delusions, and emergency-room visits as well as the toll that schizophrenia took on the family.

Part of what makes John's situation unusual is that schizophrenia usually strikes much sooner in life, typically between the ages of 16 and 25 in men, according to the B.C. Schizophrenia Society (BCSS). (In women, it tends to appear between 20 and 30.) Marion figures that part of the reason for the delay in getting a diagnosis, or at least as close to one as possible, was that - given his age and professional status - John came across as anything but a man with a troubled mind.

However, he showed many of the classic signs. According to the BCSS, symptoms fall into three categories: positive, negative, and cognitive.

The term positive symptoms refers to those that should not or do not normally occur, including hallucinations (hearing, seeing, tasting, smelling, or feeling things that aren't real) and delusions (ideas that are out of touch with reality and that can include paranoia and grandiosity).

Negative symptoms include diminished emotional responsiveness, inability to communicate, social withdrawal, poor grooming and hygiene, and impaired personal relationships.

Cognitive symptoms, meanwhile, consist of disorganized perceptions (ordinary things seem frightening or distracting), trouble understanding language, and difficulty planning and decision-making.

Schizophrenia is thought to occur because of physical and biochemical changes in the brain and affects one in 100 people. It's also treatable with medication.

"Once John was on the right antipsychotic [drug], things clicked into place," Marion says. "Within a couple of weeks, he was feeling better, and each week he felt better than the last. Throughout the whole ordeal, he had gone back to work and was able to get his life back together."

Marion says she wanted to write the book - which includes sections written by John himself, explaining what he experienced while having delusions and hallucinations - in part to have a record for their children when they're older.

"Mental illnesses do run in the families, and if one of my children do come down with this, I want them to know what happened to Dad and I want them to look at how successful he is," she says. "I don't want them to be scared or to hide it or be embarrassed about it. That's not just for my kids but for any other children. They need to know that this is something that can happen to people but that you can get help and carry on."

The other reason she wrote the book was to help people understand and accept mental illness without judging or stereotyping.

"I do believe John could have gotten faster care if he wasn't so embarrassed," Marion says. "He just didn't want to accept that something was wrong with his brain."

She says she suggested writing the book without using her and John's real names, but he wouldn't have it.

"We decided we were only encouraging stigma if we can't say who we are," Marion says. "That would defeat the whole purpose. The stigma around mental illness is so huge, but it's just like getting cancer or arthritis or diabetes, and it should be treated the same."