"Friend" at work causing massive drama

[Gettingbysomehow]

I really don't know what to do for the best. I work in the NHS with a woman in her late 50s with autism, dyslexia, dyspraxia. She isn't high functioning and quite honestly I don't know how she got her job because she is completely unable to cope. She's had numerous run ins with management and patients and all of her work is monitored.
She creates drama everyday crying, going home sick, being completely inappropriate, claiming bullying where there is none, she considers being asked to do simple tasks that are part of her job bullying and she keeps going to the union with all these complaints. None of them are ever upheld.
She was supposed to be working with me one day and I walked into our room to find her sitting in an armchair staring at the wall, she didn't say good morning or anything. I told her to go and sit in the kitchen and have a cup of tea but she often does strange things like this.
We used to be friends and she latched onto me the first day I arrived but 5 years later I can no longer stand the daily 2 hour long phone calls complaining about work.
She's even snuck into my house on a few occasions without asking me and I've come downstairs to find her wandering about so I've had to have a serious talk with her about boundaries which of course she has ignored. I keep my house locked up like fort knox now.
I've made it perfectly plain to her that I cannot deal with all her problems and I'm taking a step back. I have problems of my own and can't cope with this one sided friendship.
All well and good but now she has started accusing male staff members of sexually abusing her. She said her doctor did it as well and she got him sacked on the spot by the practice manager which is patently untrue, that's not how accusations are dealt with.
I'm concerned that male staff are not safe working alone with her. She seems to have it in for men generally. Everytime I see her she has some new dramatic story about a male member of staff touching her up.
I don't know what to do for the best, stay well out of it or report this to a management that are burying their heads In the sand about her problems.
Sorry this is so long, congrats if you have made it to the end.

I'd distance myself from her, block her phone number and don't open the door if she comes to your home. Leave management to deal with the work issues, that's what they get paid for.

Whilst I agree, I would actually report all of this to your manager OP. This is seriously disturbing stuff, and the fact that it isn't happening during working hours is irrelevant - her behaviour is triggered by the fact that she know you from work and she has no other reason to have contact with you. I would put all of this in writing, not as a grievance (unless that is what you want to do, but I suspect not - at least for now) but as a record of her behaviour. If you have any evidence, I would include copies of that. I say this because the minute you put boundaries in place, she is likely to turn against you, and you may become the subject of further unwanted behaviours. She may not be able to get in your house now, but (a) she knows where you live and (b) you can't spend your entire life locking every window and door, even in summer. I also think that there needs to be some independant record of her accusations against male staff and what she is saying - she could not only get someone sacked, but they could end up barred from their profession if she is believed.

What, if anything, your manager chooses to do about it is not your problem - but I think you should do everything it takes to protect yourself and you also have a responsibility to your colleagues who are being put at risk. To be honest, if I had a male colleague that I trusted, I would probably advise him off the record to tell his colleagues not to be alone with her.

I have whatsapp messages from her to confirm some of this stuff, including what she said about her doctor.

I would formally report it. Somebody could potentially lose their career at worst so do the right thing.
I would go NC with her unless it's work related.