Matt Willis and Emma Willis wed back in 2008, just weeks after the Busted star sought help in rehab.
The 40-year-old's addiction to alcohol and drugs has dominated most of his adult life.
And now he has made a BBC documentary, Fighting Addiction, exploring what is behind his behaviour and if science can offer hope against compulsions.
In the film, set to air next week, viewers are also given a glimpse at the impact it has had on his presenter spouse, 47.
The former Big Brother host is frequently close to tears as she tells of her fear that her husband’s addictions would kill him, plus her unease that he will relapse again.
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"It was hard for me to see how much that fear was still prevalent for her," Matt has told this week's Radio Times.
The show made the couple "realise that we still had some talking to do".
In one candid moment, Emma is filmed going through an old diary that is usually hidden away, which included a daily record of her husband’s alcohol use and the state it left him in.
"Totally wasted," read a typical entry.
Matt, who is now clean and sober, went to rehab three times before the age of 25.
While he hasn't touched alcohol since 2008, he relapsed by taking cocaine six years ago.
It came as he took part in Busted's reunion tour when his daughter Trixie, seven, was 10-months-old.
He is also father to 11-year-old son Ace and daughter Isabelle, 13, with Emma.
"Within a month I was doing six grammes on my own every day and not coming home until three in the morning," Matt says in the documentary.
Adding in the new interview, the star stated: "I had such a hateful way with myself.
"But if you look back and you can say, ‘You poor little b****r, what were you doing?’ That’s a different way of looking at the past."
Read the full interview in this week's Radio Times - out now.
Matt Willis: Fighting Addiction airs May 17 at 9pm on BBC One.
