When Shona Lidgey's husband, David, was still around, he kept the field at the back of their house cut short. Now, a year and a day after he walked out of the family home, leaving Shona and their three children, Ruth, 16, Arthur, 14, and Tom, nine, with a farewell note of four words – "Gone for a walk" – David's field is wild with flowering grasses.
The changing state of their meadow might symbolise many things – loss, dereliction or regrowth – but it is also just a field, and Shona and their children are having to get on with their lives in the tangle David left behind. The family has not heard from David, who is a doctor, since he vanished. They do not know if he is alive. But three plausible sightings of the tall 52-year-old in Leicester in one week last July led them to hope he is.
This weekend, Shona and her children will mark his disappearance by visiting the Eden Project – they can't bear to be at home. Shona hopes that the anniversary will be "some sort of turning point". "I still look outside and think he's going to come back every day, and I can't stop myself," she says. "But … well, he hasn't come back in a year – we've got to think he might not."
Shona and David met on a course for trainee GPs. Too shy to chat, she wrote him a letter, asking him out. After they got together, they travelled to India for six months; David's photographs of their travels still hang in the living room. They married and both worked as doctors in south London before relocating to Norfolk five years ago.
Shona learned of David's depression after a few months together. He resisted seeking outside help; instead, he prescribed himself antidepressants and wouldn't discuss it with anyone apart from Shona. "He didn't want anyone to know. He felt it was a weakness and yet he was very good at treating people with depression – very sympathetic. People have phoned me to say he really helped them a lot," she says.
Last year, his usual dip of two to four months continued for six. "He was so separate from the family because of his depression," says Shona.
On the day he vanished, David drove the children to school, talking about a disappearance earlier that month, and promised he wouldn't do it again. A neighbour saw him return at 9.10am, and by the time Shona got home from work at 3pm there was the note on the table. At 7pm, she called his mobile, and heard it ringing in the house. "It was horrible," she says.
David had not taken his wallet, passport, money, or his much-loved Volvo, and they found the multi-tool device he always wore on his belt – a present from his wife – in their bedroom. "It was almost like a deliberate, 'I'm leaving all this,'" says Shona. Since he left, police know there has been no money withdrawn from his savings accounts and no crossing of borders.
Does Shona believe he is still alive? "I do," she says. He talked about killing himself in the past and she checked with the waterways about how long it takes for bodies to resurface. After dispatching "missing" posters to David's favourite places, because "he loved the past and had very fond places he loved revisiting", potential sightings gave her hope.
He is fit, loves travelling and could easily do cash-in-hand labouring. "He probably has just gone for a long walk," she says. She wonders how he is coping emotionally, and if he is being supported by someone else. "He's always said he's very loyal and he would never have an affair. I don't know. That's one of the things I think about and it makes me very upset. Why torture yourself with things you can't know?"
What does such a disappearance – bringing, perhaps, the grief of a bereavement and the anger of a divorce but also profound uncertainty – do to family life?
"It's just been really sad a lot of the time," says Shona. "The children have been amazing. I've cried a lot, and they have, but they've really tried to keep me going." But the family has also been forced to focus on other things. In October last year, Arthur fell dangerously ill. He was in hospital for four months but is now home and recovering; the family also feel better after a spell of therapy. "We have gained a lot in understanding ourselves as a family and understanding our relationship with David," says Shona. Arthur felt closest to his dad, she says, and was "protective of him"; now, he feels more that his dad's disappearance was David's choice and not because their family had done something wrong.
Do they feel angry? Tom has been the angriest "because he sees us being upset and doesn't like it. It's quite hard for him to say he misses him but he really does," says Shona. "I didn't feel angry after the first three weeks because I just felt so sad. The next time I felt angry was when Arthur was ill. I felt so angry David wasn't there for him. We won't ever recover or be the same after this. It has damaged us all. And I know he didn't mean to do that. I think he thinks we're better off without him."
If she could talk to him, what would she say? "We all love him, and we love him for himself completely, not for anything he gives us or does. We're broken by his loss, and miss him hugely, and want to have contact with him again." Shona feels fortunate to have a job that enables her to pay their mortgage. Even if she wanted to, she can't sell their house until seven years after David's disappearance – when the law declares a missing person is dead.
The children are rearranging their home gradually. David's books, CDs and pictures of his heroes – who include John Betjeman, Peter Finch, Nelson and Nick Drake ("his heroes are tragic heroes," says Shona) – still adorn the walls of one room, but in the centre is a new table-tennis table.
Shona is in limbo but feels that the children are more positive. "They live around the gap. They are not living each day thinking he's going to come home." If he does, she knows it will be difficult to have a simple happy ending. "We've all changed a lot, and he'll have changed a lot. I keep thinking of all the happy times and missing him terribly, but of course it wouldn't be like that. It would be very traumatic."
She still desperately wants him to come back. She can't move on "because it feels like I'm losing so much if I do. As I get better, I'll feel you can't lose the past, it's still there, but the future doesn't contain him because he's removed himself from it for me."
What would she do if he walked in? "I'd want to cuddle him. I know it's silly, but I was sad I didn't have physical contact with him to say goodbye. And then just shout at him, probably. I don't know. You stop yourself from thinking about it because it creates hopes and these aren't realistic. But I know I'd want to cuddle him."
• If you have any information, visit missingpeople.org.uk, call the helpline 0500 700 700 or contact Norfolk police on 0845 456 4567
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