I don't know what to do

[Ksjs3]

It's gonna be long so please bare with me.
My 16 year old daughter is driving me mental. She is autistic and suspect adhd.
She's at sixth form college and failing big. Her attendance is at 55%, she's failing two of her three subjects. She laughed at the targets they've set, said its not her fault because xyz. She's at risk of losing her place for next year and blames everyone else for this because they "don't do anything to help her". She's been offered numerous avenues of support at college as well as offers to use their counselling services but she won't engage. We've tried camhs, but they've twice discharged her and said they don't see anything she needs their level of support for.
She told them she thinks she's bipolar, they said there wasn't any indicators there and she was fuming they didn't agree with her. (For the record, I agree that there isn't any indication that screams bipolar). She is waiting for appts to test for eds and pots (which I do believe she has). She has been saying she keeps vomiting for no reason, then when I said we should get you an appt she first said she didn't need it, it's probably just anxiety, then when I hadn't made an emergency appt and said I was going to make it with the gp, she got angry that i wasn't making an appt right then and there (at 9pm), then said "I didn't even want an appt, I'm done" and stormed out.
If I try to support with college, or health issues, im wrong unless I completely agree with what she says or wants. Nothing i say or do is right. I've said if she gets kicked off her course she'll have to look for an new course and she said "no one will take me" so I said then you'll have to look at a job "but it's illegal so I can't get a job without also studying" (I've checked this and although it's law, its not enforced so yes, she can).
I'm looking at paying for private therapy to see if that's any good but I really need some advice and support because I cNt keep going on like this. This behaviour isn't new, it's been all the way through school and I'm exhausted.
I have two boys to take care of (15 and 10) and they've seen and heard too many screaming matches and arguments, as well as my mum who we live with as she is disabled and chronically ill, and i work full time. I can't do it anymore

Could there be an issue at college that you're not aware of? It sounds like she just doesn't want to go. I used to refuse to go to school or pretend I was sick because I was bullied and no one did anything about it. Unfortunately, if she won't engage with any help being offered, there's not a lot you can do.

I don't think it's illegal to work full time at 16. You're only expected to complete school at 16 and then proceed to work, college or apprenticeship.

Are there any careers she's interested in? Perhaps she could get an apprenticeship or volunteer.

I would make it clear that you expect her to be doing something productive with her time, and you won't tolerate her doing nothing all day if she doesn't want to continue with education. Provide her with the basics and if she wants new makeup, certain clothes or fun money, she'll have to pay for it herself if she's no longer going to college.

Of course, I don't know you and have no idea of the extent DD's autism is. Only you know if she has any limitations and what she's totally capable of doing. My suggestions could be completely unreasonable!

Thanks for your response!
It's not that there's issues at college because it's the same across the board (She's no different at home when it comes to doing anything that she doesn't want to... I can't see her bedroom floor... at all) she was also the same at school. She blames mental health for when she doesn't go to college or why she's failing, but it only seems to affect the things she doesn't want to do as opposed to when it's something she does so I feel rather than it being mh, it's more of a demand problem. (Not that i don't think she struggles with her mh, she does... but I think she also uses it to avoid responsibility). I've tried to explain to her she can't just sit about at home and do nothing and if her mh is bad then 1. That will make it worse and 2. She needs to start engaging with the support being offered x

I was the same. If I was told to something, there had to be a huge drama and tantrum, and I'd be a vile creature. I hated being told what to do, what time to be home etc! I was told in no uncertain terms that if I wasn't going to college, then I had to get a job. So I got a job in a salon and went to hairdressing college once a week to train.

It's hard to know what to do for the best. It sounds like it could just be her personality that she doesn't like being told. That, and laziness (as was/am I!) Is she receiving help for MH?

I was also similar but my parents were old school so if I gave them shit I'd get a hiding.
We tried camhs but they discharged her and directed her to off the record and various other things to try but she refused to even entertain it. College have offered her counselling but she refused to try it. I'm on the process of finding her a private therapist x