The former footballer supported his pop star partner after she spiralled into a deep depression and was admitted to a psychiatric hospital.
Frankie, 31, spent a month at the private Nightingale Hospital in London getting the help she needed, with Wayne travelling back and forth from Manchester to visit her.
The singer has now opened up about the toll her illness took on her husband, revealing his weight plunged and he was left battling demons of his own.
It was heightened by the fact that they decided to keep Frankie’s hospital stint a secret – even from her own family.
In her book Open: Why Asking For Help Can Save Your Life, she wrote: “I had decided not to tell my family about my stay in hospital, at least not at first. I just couldn’t…
“So it was Wayne who took me to the Nightingale Hospital in Central London. He was my constant, the person who knew me inside out and had seen me at my worst and most vulnerable…
“Wayne would visit whenever he could between training and playing football for Manchester City.
“Learning about my illness and realising he couldn’t make me happy was a lot for him to take on.”
She went on to describe the effect it had on Wayne’s own health as he struggled to support her.
Frankie added: “He lost a lot of weight around then and ended up the lightest he has ever been.
“Now we think it was due to the stress, but at the time I didn’t notice how badly everything was affecting him.
As we’ve spoken about my breakdown over the years since, the stress it caused him has come out in both anger and sadness.”
She made a recovery and has credited medication and therapy with helping her through her depression.
However, she still battles side effects including low libido, which has also put a strain on her marriage.
She went on: “The side-effects of these medicines are often a big problem, too. Typically, they result in headaches , nausea, tiredness, low — or no — libido, a horrendously dry mouth, weight gain, constipation and, most embarrassing of all, involuntary muscle spasms.
“Day-to-day life with anxiety and depression is hard enough already, so these horrible extras don’t make things any easier…
“It must be very difficult for Wayne to accept that my lack of interest in sex is because of my medication and has nothing to do with my feelings for him, or how much I am attracted to him.”
The couple married in 2014 and are parents to two sons.
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