The number of callers to the charity SANE’s telephone helpline has increased by 200% since the lockdown began.
Marjorie Wallace, who founded the charity some 35 years ago, has never known anything like it.
"In the last month the levels of distress, the acute anxiety and the feelings of helplessness have reached a new threshold," she says.
For people with mental health problems, the increased isolation of lockdown is the last thing they need.
So much of the successful management of their illness is based on engaging with society, getting out and meeting up with people, maintaining a sense of purpose and self-worth through work or relationships with friends and family.
Lockdown has upset all of that.
Sonia Sanghvi has been living with acute depression since her teens.
She has always lived alone and so had thought that lockdown would be something she could handle.
She was wrong.
Not being able to go to work, or even enjoy the routine of going to get a coffee round the corner from her flat, has left her facing old demons, and self-harm.
"There is the possibility of hurting yourself," she told me.
"It’s not a great coping mechanism, but it is a coping mechanism. And it’s one I’ve been living with for over 20 years."
In data shared by SANE with ITV News, the charity reports that 85 percent of the people who have contacted its helpline during lockdown are new callers.
In the places where people are still allowed to interact in this outbreak, there are new strains on mental health.
Kay Timbrell is a checkout supervisor in one of the big supermarket chains.
She’s been put in charge of making sure customers observe social distancing measures at her store.
For the first time in her 26-year career, she’s sought counselling for overwhelming levels of anxiety.
"I get a tightening feeling," she says, wringing her hands together in front of her chest.
"And a sense that I’m losing control over my emotions when I see the measures being completely disregarded."
SANE says the closure or cessation of mental health services during lockdown is a critical issue, particularly for people with severe mental health problems.
If they are no longer being visited by their community mental health teams, then the risk of self-harm or suicide increases.
The charity also says that a lot of callers have told them that they are not accessing primary care services because they don’t want to "bother" GPs at such a busy time for the NHS.
Much like physical injury, the longer mental health problems go untreated, the worse they get.
Lockdown has made it much more difficult, but contact with sufferers has to be made, and kept.
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