Zoë Ball on how the loss of boyfriend Billy Yates motivated her Sport Relief challenge

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This time last year, Zoë and Billy were an item. The Radio 2 DJ and Strictly presenter had, in her father’s words, found a new lease of life with the television cameraman, who hailed from Darwen but who lived in London and worked on Antiques Roadshow. After the trauma of the breakdown of her 17-year marriage to superstar DJ Norman Cook in 2016, Zoë was rebuilding her life. But then, shockingly, Billy ended his.

Billy Yates died alone at his Putney home in May last year. Zoë was among the first to discover what had happened. In the aftershock, she left the airwaves, reappearing four weeks later to open her Radio 2 show with a Northern Soul classic dedicated to Billy: Do I Love You (Indeed I Do) by Frank Wilson.

Aged just 40 when he took his own life, Billy had suffered with depression. “At the time Billy came into my life, I didn’t know how to help,” she says. “I knew he had lived with depression for a long time. But he was a big strong guy. He did the Iron Man, he loved cycling 50 miles a day, he was the life and soul of the party when he was on the crew, he was so much fun. To see a man like that crumble under the pressure was heartbreaking to watch.”

The pain is still raw, ten months on, and despite the Lycra outfit and welcoming smile Zoë is wearing for her RT cover shoot, and the warm hugs she dispenses, the 47-year-old is fragile and in a reflective mood. She has never talked openly about Billy and when the mask slips, revisiting their relationship is clearly difficult. But she is doing so very publicly this week.

“I knew how much pain he was in,” she reveals in a one-off BBC1 documentary on Wednesday evening. “He couldn’t make sense of what was happening to him. It was almost like a change of light, you could see the pain come into his eyes. You wanted to say, ‘Come on. Stay with me, stay with me. Let’s get you out of this headspace.’ But it was harder and harder to do that.”

In her quest to understand the illness that afflicted her boyfriend – and to raise awareness of mental health – she signed up for her cycling challenge, which is one of the highlights of Friday night’s Sport Relief programme. Riding from Blackpool to Brighton is no mean feat for a novice cyclist (it is not, as the jokers say, all downhill). But then Zoë is nothing if not doggedly determined. “When I lost Billy I wanted to do something, and I felt with my platform there was a chance to help.

“Billy didn’t tell me about his depression at the beginning, it’s only when you get to know someone that they really share stuff like that. Any other illness and you have time off work, but there is a lot of stigma around mental illness. It’s frightening to talk about it. The people suffering don’t want sympathy. Although I wasn’t surprised when he eventually told me. I could see there was some sadness. I tried my best to help. But I look back and think, ‘I’m not sure I did the right thing.”

So, what would she have done differently? “You can’t just sit down with someone when they are that poorly and say, ‘I want to help.’ There is no quick fix. I’d say things like, ‘If you exercise, go outside, see someone you love, it might help.’ But it didn’t. And the therapy he had didn’t even touch the sides.”

Around 6,000 families lose someone to suicide in the UK every year. But it’s perhaps a more alarming statistic that the biggest killer of men in the UK under the age of 45 is suicide. “One in four of us will experience mental illness,” says Zoë. “But the number of young men killing themselves is shocking. Why? A lot of men I have spoken to have said it’s very confusing being a modern man. You want to be sensitive but also strong. You can’t win. It’s really hard trying to be both.”

But this is about more than just men being confused, it’s an illness. “Yes, this a disease, and men suffering with depression need help. It takes the right person to break through to someone who has been brave enough to reach out.” Her worry is that finding the right people to help is so difficult – the NHS is stretched and resources are limited, drugs may provide short-term relief but not a long-term answer and independently funded mental health projects that can provide specialist help and support are thin on the ground and short of money.

“We are so busy looking after our body – we drink less, we take vitamins, we exercise – but looking after the mind is taken for granted. From my experience with Billy it was very difficult for him to find support. There is very little on offer other than anti-depressants and a bit of counselling.”

In her documentary she meets Penny Johnson, a mother whose son Jamie killed himself at the age of 19. Penny went on to found the Tomorrow Project, a suicide prevention service run by Harmless, a charity funded by Sport Relief. “We talked about our boys,” says Zoë. “We agreed that we shouldn’t let their deaths be in vain. If me doing this challenge helps one other person seek help, then it has been worth it. If one other family doesn’t have to go through what Billy’s family have gone through, then this is all worth it.”

Bereavement hurts, whatever the circumstances, but suicide is “really cruel”, as Zoë puts it. “Talk to people who have lost loved ones to suicide and you are always left feeling that there was something else you could have done. The horror is unbelievable.

“There are moments – I had one this morning – when I can’t believe any of this happened. I’m in the middle of this challenge and Billy’s gone. That never leaves you. That and the heartbreak, and the fact you couldn’t save them. It’s true for Billy’s mum and dad and his sisters and friends, too. They are all in pain. Especially his male friends. The ripple effect is dangerous. It can happen again. It’s scary.”

Does she still reproach herself? “Even now I sometimes think, ‘I’m a resourceful woman, I’m a bright woman… why could I not save him?’ And then I have to stop and say, ‘Everyone who loved him knew. None of us found an answer, none of us saved him. To move forward you have to accept that. Which is very difficult. But I take comfort from the fact he is no longer in pain. He struggled every day and now he is at peace. The pain has stopped for him.

“And I remember all the glorious things about him. He was a funny man, so full of love. I remember looking around at his funeral and everyone was talking about him and I thought: ‘He would have hated this.’ He hated being the centre of attention. He hated a fuss. He hated the cameras. He hated all that stuff.”

What, you wonder, would Billy have made of her charity bike ride? “He would be pissing himself laughing that I’m in Lycra on a bloody bicycle. He would find it hilariously funny and frankly unbelievable. But I like to think he would say that if there’s someone out there we could help not be in such a desperate state as he was, he would be grateful for that. So, I hope he would be pleased. Although I have cursed him a few times, especially going uphill: ‘You sod! I’m doing this because of you!’ In grief, a dark sense of humour is handy at the lowest moments. He had a wicked sense of humour.”

Not that riding 350 miles in five days is a joke, especially if the last time you regularly rode a bike was four decades ago. “I may be 47 but I feel 63! But once I got over my fear of the road, my fear of junctions, the feeling of ‘Argggh! There’s another hill coming…’ I have been getting off my bike feeling high. I’m sore – the key is no knickers, just padded pants and serious undercarriage buttering to avoid chafing. But I’m also slightly euphoric.” She smiles. In the documentary there are tears (although she’s quick to point out “I’m not bawling my eyes out”) and talking to her now it feels as though they are never far away.

How is she? “I’m getting stronger. I’m a tough old cookie. My family have been through a lot. There are moments when you least expect it when grief catches you. But the main thing for me is I’ve found people who have been through this and are doing better. They’ve found some hope. That’s the biggest thing for me – that there is hope. Otherwise what are we doing this for?”

As for Billy, she carries his memory with her. The rose tattoo visible just above her wrist echoes one he had on his arm. “He’s missed terribly. When you lose someone like that you feel they are always with you. It’s not been long.”

She visits Darwen every few weeks, where Billy’s mum and dad still live, to see his family. “He used to go up to Darwen Tower. On his birthday in September I walked up there with his friends and we set off fireworks and carved a B into the rock at the top. It’s a beautiful place to reflect. I find him in the sky. Whenever there is a blue sky it feels like he’s here.

“I don’t think you ever get closure. It’s something that’s part of me now. He will always be in my heart. Hopefully this isn’t the end, but the beginning of me doing something to help.”

Zoë Ball’s Hardest Road Home airs on Wednesday 21st March at 9pm on BBC1. Sport Relief is on Friday 23rd March at 7pm on BBC1