I would speak with her dad and explain that you would like to look at private options potentially.
A full ASD assessment and diagnosis is important. You're going to get pointless advice from many professionals and suggestions of BPD or ineffectual parenting! What even is BPD. It's another made up waste basket diagnosis that means nothing. A significantly high number of adult females told BPD actually turned out to be Autistic.
There is no doubt in my mind here on this one; she's Neurodivergent.
If you want access to financial support as she gets older then a diagnosis is important, help and accomodation in a work environment if she is ever able to manage that, access to supported housing potentially, issues in the criminal justice system if she ends up getting arrested or into criminality. For her own understanding and well being, for access to support such as psychiatry potentially.
I can't stress enough how important I believe it is for everyone to know and have that diagnosis. You will also potentially be gaslit to high hell when nothing works anymore and have pointless suggestions such as ' bpd'.
SSRIs can be very difficult to begin the first 6 weeks. I took them in my youth and had diazepam alongside them only for the first 4 weeks to help side effects. Diazepam is dangerously addictive.
You'll wait an eternity on the NHS for assessment for Autism. If your ex can help fund it, that's a start.
The problem will be convincing your daughter. I don't care if she's Autistic, and I say this about my son. You go around hitting people consistently then you'll face the consequences of assault. If she's willing to engage with assessments and trying out new meds that's great and possibly a bargaining took. Eg if you don't engage then I will be calling the Police the next time.
I don't think it's fair you are lumbered with all this alone. I would absolutely need respite via dad. Again, I wouldn't care too much if she doesn't like it. He's getting an easy ride here whilst you get battered? No way. He needs to step it up. Of course she'd be horrified if people knew, so take some responsibility and work with your mum ( assessment, medication etc) and stop being a horrible abuser. I fear that we are really in danger as parents of Autistic/ ADHD kids of excusing violence. Then what have we done when they potentially go off and kill someone.
If she did follow through on her threat, I really believe that's out of your control. I find it incredibly manipulative. I lost a parent this way and there were no threats, it was just done. I know how scary that feels but she knows full well you can be manipulated - even if she is feeling severely depressed.
No excuses. I have endured hell, I've behaved appallingly at times but I have always tried to take responsibility. When you let this crap off the hook, no matter what the cause, you are enabling a dangerous individual.
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