Where do I stand here?

Some of you may know, I'm underpaid at work and on the verge of burnout.

I work for a small business, 5 of us, and we all get on. Marketing. 

I sent an email mentioning feeling burnt out, would like to clarify my workload on an upcoming project, and a review of my compensation. I mentioned my mental health, that this burnout feeling is getting worse and I'm struggling to manage it. 

Work know I am autistic, they have been supportive of me, and have accepted that I struggle to do things such as socialising, networking, and phone calls. 

I worked on an email with my dad today whilst working from home, and the reply I got... I just burst into tears.

My boss referred to me asking for support with phone calls as "grievances", nowhere in any email had I even brought support up in the first place. I simply asked for support with my workload, clarification on responsibilties, and a review of my pay.

I had (obviously wrongly assumed) that requests for support, which wer happily accepted, were reasonable adjustments. But now they are being classed as me having "grievances."

There is a paper trail to back what I'm saying up, and I have a meeting on Monday to discuss everything. 

My head is spinning, and honestly they are making me feel like my disability is a difficulty that the business has to navigate, and that because I'm disabled, I'm not good enough at my job.

I feel heartbroken, I love my job, my boss said she classes me as like a sister to her, and then this... I'm not even sure what to say.

I'm terrified about Monday, I don't handle any of this well.