The inquest into a mother of five who was found dead in Accrington heard she used alcohol and drugs to try to manage violent flashbacks.
Heidi Marie Wilson, 41, of no fixed abode, moved to Chorley in 2023 after she fled from domestic violence.
Blackburn Town Hall heard how Heidi was known to mental health services such as her GP and Lancashire and Cumbria's Home Based Treatment NHS team.
She struggled with issues such as self harm, PTSD, and ADHD in the past.
On Tuesday, January 26, Wilson attended a flat in Gladstone Heights on Eagle Street, after she was invited by someone she had known from her rehabilitation meetings.
Heidi had been clean from heroin for two years, but had also struggled with alcohol and other drugs such as crack cocaine.
She told the staff from the NHS she "tried to manage her flashbacks" of domestic violence with the substances.
Two witnesses who frequently attended Gladstone Heights said they had seen Heidi 'asleep' on the couch in a flat.
They told the owner of the property to ensure Heidi was well, to which he said she was 'asleep'.
On Friday, January 30, the witnesses checked up on Heidi, after they were concerned she was 'asleep for four days'.
They noticed she was 'cold to the touch' and rang the police, who announced she was dead at the scene.
A post-mortem examination showed that Heidi had marks that looked like dots from an injection on her arm and groin, and traces of cocaine, diazepam, morphine and heroin in her system.
The court heard how her family, who are from Wigan, were unaware she had moved to Accrington due to her unhappiness in Chorley.
In a statement, her sister Sarah said: "She struggled from a young age with learning difficulties that in today's standards she would have had help for.
"She was a great mum."
Coroner Mark William gave a conclusion of death as drug-related.
He said: "Heidi struggled from many issues including domestic violence and drugs in the past. She had been able to stay away from drugs for two years, and no one really knew why she came to Accrington.
"I offer my sincere condolences to the family."
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