I kind of what some answers to this once and for all. I was diagnosed with Asperger's at very nearly 16 (I'm now 21) having struggled all my life with anxiety and depression, had an eating disorder etc (all the classic Aspie girl stuff). About two years later, I had a mental health crisis. With hindsight, it was a result of issues I'd always had, but my moods and behaviour became more and more erratic over several months - I felt like death; I remember lying in dark rooms in excruciating mental pain, carefully planning how I would kill myself, sitting awake all night staring at walls with glazed eyes, hiding in cupboards at school unable to lift my head but then running around a few hours later, buying £100 worth of cakes and giggling and hallucinating diamonds on the pavement. Long story short, I ended up collapsed on the floor in the middle of town having run away from school, bleeding, screaming, I'd written the word 'liar' all over myself in marker pen, I was hearing voices, believing people were out to kill me, and I ended up having to be restrained and put in a police car; I was then taken home, and for some reason neither I or my family understand I was not offered any more intensive treatment (despite the police arranging a mental health act assessment: it either never happened or I don't remember it! I do remember a really horrible man coming round from the primary care mental health service the following day and utterly victim-blaming me, saying it was 'about choices' and all I needed to do was 'make an effort', and telling me I was having delusional thoughts in a very accusing tone which is not what you're meant to do when someone is having a psychotic episode). My GP just gave my parents a packet of Valium and told them to give it to me every four hours, including throughout the night, with the anti-psychotics I had already been prescribed by a private psychiatrist I was seeing, and told them to 'keep me safe and let nature take its course', so essentially my parents, who had jobs and my two younger sisters to look after, had to become psychiatric nurses in their own home. The worst thing for me was the effect this had on my family, and that the social services called a couple of days later to see if my sisters were safe from their out-of-control sister, when I would never lay a finger on my little sisters whether I was in crisis or not; I was the one in danger and I didn't see an NHS mental health professional for a month after seeing the vile primary care guy. But that's life I suppose.
About four years on, I've had other problems, including an overnight admission to A&E due to self-harm and suicidal behaviour (worst night of my life and I've had quite a few bad nights; I can't even think of it without getting upset) while they called the psychiatric hospital to discuss admission (the hospital said no as they didn't think being on a ward would help me long-term; they told the general hospital where I was to keep me in so I was safe overnight and that they'd reassess in a few days; luckily my situation calmed down and I was just referred back to the CMHT). I've had many other so-called paranoid and delusional thoughts, and I've had crises that only people close to me know about, like when I went through a phase of trying to scar my face (even professionals didn't know about that until afterwards. I did actually end up scarring my face: I've got a little scar on my cheek you can see when I haven't got make-up on, but luckily most of the facial cuts healed without leaving any marks). However, I'm doing pretty well right now: I'm a published poet and short fiction writer - I'm passionate about my writing and I'm told I'm good at it; I'm getting a poetry pamphlet (which is like a small collection of poems) published by a small poetry press soon - I'm managing to lose weight healthily (I've been quite significantly overweight due to binge-eating which the meds haven't helped with) and I'm keeping fit, exercising every day, I'm reading lots and I'm starting at uni next month having been desperate to go for a long time. Most importantly, I have some amazing friends (I've had some cr*ppy ones too, but I'm OK with that as they've taught me some good lessons). I'm now on 550mg of quetiapine (which is a moderate-to-high dose) and I hate how groggy and yucky it makes me feel - it's like waking up every day with a hangover! - but it does help; I don't know where I'd be without it. As well as the Asperger's, I am diagnosed with borderline personality disorder and I identify very strongly with this diagnosis - I have no issue with it, and it has got me support from secondary mental health services including DBT (Dialectical Behaviour Therapy) which I've found extremely helpful without them needing to adapt it for autism or anything - but I get a lot of people from the autism community saying, 'That's often a misdiagnosis, particularly with girls and women on the spectrum, they'll have got it wrong, you don't have BPD, you have autism and that's that.' However, my parents and mental health professionals I've worked with think I definitely have additional mental difficulties, and that psychosis is never a part of autism; if an autistic person becomes psychotic it means they've got comorbid mental health problems. I guess I was wondering if you guys knew anything about this? I've been so confused for so long and I know I shouldn't base too much importance on 'labels' as it were, but it gets to me - I can't help it. I just want to be able to understand my mind!
Thanks for reading.
Firstly, I'm sorry to hear about what you've been through. You and your family have been very badly let down by the people who were supposed to be helping you.
As far as I know from several years on forums like this one, you're right, psychosis is not inherent to autism. I don't know BPD well enough to comment on your presentation, but I've seen enough to know that it unfortunately does seem to have a particular stigma attached to it, though I don't know of any clear evidence that autism is misdiagnosed as BPD any more than any other condition which sometimes has similar traits. The "sometimes" is important; you've been receiving care for some time from multiple professionals, and even more importantly, the support for BPD is helping you; so I see no reason to doubt that a dual diagnosis would be appropriate from what you've told us.
If you've not tried it already, Wrong Planet is an autism forum with a dedicated section for people with other conditions, whether also autistic or not. That one might not suit you, but I think it may be worth a bit of searching and lurking to see if there is forum or support group where you can find people with real experience of living with a dual diagnosis.