The Hampshire woman, who has a legal right to anonymity, was sexually assaulted in 2012 and been under the care of Southern Health NHS Foundation Trust from 2014-2015, and then since 2018 after a relapse.
But she says her experience with the health trust over the past four years has been a persistent obstacle to recovery, with assessments refused and accusations made by phone operators.
Now, she is suing for a data protection breach after claims that Southern Health even lost some of her medical documents.
The woman, who has shared her experiences with the Local Democracy Reporting Service, said: 'My mental health problems started after I was sexually assaulted.
'Under Southern Health I have been ping-ponged by the community mental health team to different services - including Autism Hampshire, even though I don't have autism.
'The trust has also lost 39 pages of my rape crisis paperwork.
'Since I relapsed, Southern Health has made me feel worse, not better.'
Since being assaulted, the 44-year-old woman has been diagnosed with complex PTSD, severe depersonalisation and derealisation, mild amnesia and mild identity confusion.
Buy these conditions were all diagnosed by Hampshire and Isle of Wight CCG, after Southern Health refused to assess her.
She said: 'Southern Health said they wouldn't support the assessment - and then told me it was a 'slap in the face' when the CCG stepped up to sort it instead.
'It felt like they did everything in their power to not get me this assessment.
'I've also been laughed at down the phone and one woman asked me if I had got things all wrong 'because of my mental health'.
'I'm mentally ill, not two years old.'
The 44-year-old was full of praise for the CCG, but says Southern Health has a long way to go.
The legal claim has been filed by Chris Rudd Solicitors, based in Warrington.
The Information Commissioner's Office (ICO) has already confirmed that the trust failed to comply with data protection obligations.
As for the woman herself, she is starting new treatment in the near future, and a specialist report from the Beacon House trauma team in Chichester has hailed her strength and persistence.
'This whole ordeal has really set me back in life,' she said.
'When you're referred to an NHS trust that specialises in mental health, that's the last thing you expect.'
A spokesman Southern Health NHS Foundation Trust said the trust could not comment on ongoing legal proceedings.