Mia spends much of her time staring out her bedroom window, the view dominated by a nearby housing block.

With no lift, the only way the 14-year-old can leave her second-floor flat is by shuffling down the stairs on her bottom.

It’s been years since Mia felt ordinary, a near lifelong sense that she didn’t fit in. It all got too much for her a few months ago when she made a suicide attempt that has left her with paraplegia, unable to move the lower part of her body – and she now needs a wheelchair.

“I can’t change the past now,” Mia says, “it feels spiteful that I can only look at the future, and that I have no clue what is going to happen.”

The teenager’s story, indeed much of her life, will be familiar to the many families who have struggled to navigate the creaking mental health system, leaving them feeling their concerns have been downplayed or dismissed.

BBC analysis of official NHS data suggests that more than half of young people who get psychiatric support finish their course of treatment with no improvement in their health.

Meanwhile, the number of young people who report having poor mental health rose from one in nine to one in five between 2017 and 2023, according to a recent report by the charity Mind. It says that last year only a third of those were able to access treatment.

Mia’s mother, Christina, first sought help for her daughter when she was five years old and had developed an exact ritual for each morning, getting dressed in a particular order and spending up to two hours in the bathroom.

Within months, Mia was told she had obsessive-compulsive disorder (OCD). But they felt the diagnosis was wrong, and life didn’t get any easier.

“When you’re a seven-year-old child and you can’t properly understand why you feel so different and so isolated, it’s obviously going to impact you growing up,” Mia recalls.

“There’s never truly [been] anywhere that I feel I belong.”

Mia and her mother became convinced she was on the autism spectrum and Christina pushed for an assessment at the local children’s mental health service in Islington, north London.

On two separate occasions, Mia didn’t score highly enough in initial screenings to trigger a formal assessment.

Her mother believes the test was geared towards diagnosing boys, which the service provider says it has now improved in line with increased understanding nationally of how autism presents itself in girls.

As Mia struggled on, finding it difficult to make friends, Christina approached her primary school’s special educational needs teacher, her local social work department and mental health services, desperate for support.

“I was ignored and made to feel like a neurotic mum – nobody was listening,” Christina says.

“I felt they didn’t understand her needs. I don’t think they knew how to support her.”

Towards the end of her first year in secondary school, Christina was contacted by a teacher who said the school believed Mia was autistic. This time an assessment was made, which diagnosed the condition. It helped with her education. Mia was given extra support during exams and with homework. But it didn’t lead to a huge shift in psychiatric help, says Christina.

There was a stop-start nature to the help Mia received over the years. An occasional eight-week course of Cognitive Behavioural Therapy (CBT), then nothing for a few months, then some sessions with a different therapist.

Christina says appointments would sometimes be cancelled as the therapist was ill, or changed jobs, leaving Mia feeling little progress was being made.

Whittington Health said the care it provided to Mia was “in line with national guidance”.

“Such care is inherently complex and we regret that her difficulties continued to escalate,” it said.

An NHS England spokesperson added: “Our thoughts are with Mia and her family. The NHS is determined to improve children’s mental health and autism services… because we know there are some people waiting too long for care.”

The Care Quality Commission – which is responsible for inspecting NHS hospitals – says mental health services are struggling with recruitment, including the right mix of staff, “all of which are having an impact on capacity, and the availability and regularity of appointments”.

It encouraged the NHS to “actively involve parents in their child’s care decisions” adding that “addressing their concerns promptly is critical to safety”.

It’s a recommendation that Christina dearly wishes had been acted on much earlier.

In the summer of 2023, when Mia’s health deteriorated further, she was prescribed a course of anti-depressants. She was told the medication could lead to her putting on weight, which infuriated Christina, as her daughter then developed an eating disorder.

Mia also started to make suicide attempts – on one occasion, her mother had to physically restrain her to keep her safe.

In March, two days after her therapist cancelled an appointment, Mia tried to end her life, which left her with severe spinal injuries.

“I felt I was falling behind with school, with friends. I felt like I was falling behind in the world, really, and sometimes it feels like it’s really hard to stay afloat.”

After her suicide attempt, Mia says for about a month she couldn’t move or sit up.

“I was in constant pain. I was on medication, just to not cry. And then I had to relearn a lot – basic things like sitting up and eventually standing, even though it’s still very much assisted. And I had to relearn certain motor skills. And then I had to adjust to life in a wheelchair and managing being paraplegic and feeling like it’s never going to get any better,” she says.

Monthly data published by NHS England shows that mental health services often struggle to provide the right care to young people. Since April 2023, psychiatric services have assessed the impact of 94,802 treatments that have been offered to young people to see how their mental health has changed. They show that:

• 44,035 (46%) showed improvements;

• 9,449 (10%) showed measurable deterioration;

• 41,318 (44%) showed no measurable change in health.

Added together, 54% of scores showed either no improvement or a deterioration.

Responding to the BBC’s analysis of the data, NHS England said: “Not everyone can get better and stabilising symptoms gives opportunities to re-assess patient needs and look at new options. If you are struggling with your mental health do come forward for help.”

Mia does a series of daily exercises to strengthen her muscles and maintain movement. A high-performing student, she desperately misses school. The mental health service is now giving her a range of different therapies, which she sees as coming “far too late”.

There is now another challenge, however. Mia’s block of flats has no lift, and a request to install a stairlift has been delayed for months as the housing association questions whether it would be a fire hazard. To attend therapy or hospital appointments, Mia has to shuffle down two flights of stairs on her bottom, while her mother carries her wheelchair.

Southern Housing, which owns the block, told the BBC it does not have any adapted housing that meets Mia’s needs, and that their fire safety specialist is working alongside a lift surveyor and the occupational therapy team at Islington Council “to investigate whether this is possible”.

Islington Council said: “Mia has a dedicated social worker and the council is working hard to make Mia’s current home more suitable. We have offered three alternative accessible properties, which unfortunately, have not met the family’s specific needs. We are committed to continuing the search.”

Mia’s neat and tidy bedroom has become her refuge. But in time, she hopes to have the confidence to face the outside world.

“No matter how odd or strange you feel for feeling and thinking the thoughts you do, the most helpful thing you can do for yourself is to speak to someone else. If you never tell anyone, they’ll never be able to help,” she says.

“One day, I’m going to be proud of myself.

“That’s what I’m looking towards, a place where I can be proud at how much I’ve overcome.”

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