Complaints - how do I set out a letter to explain?

Hello, I've been using this resource to help me successfully appeal against 2 decisions (they told me to make a new claim from the date I lodged the appeal, which, unsurprisingly, was rejected, so had to make another appeal - bit confusing). It has been a nightmare. Was in receipt of lower PIP from 2013-15, just as I was turning a corner I was reassessed. The ATOS examiner's report was a pack of lies. The plug was pulled and so began the reclaiming process. This started in Nov 2015. I am now 2 years behind, I have become more ill and life is just rubbish.

I won at tribunal on 3rd March 17 -
I received back dated payments to cover the 1st claim dates, up to March 2016. After 3 weeks I phoned to see what was happening with the 2nd dates. DWP denied receiving it. I phoned the tribunal service who told me both decision notices were emailed to the same office at the DWP at the same time - since confirmed in writing.
DWP would not accept my copy of the decision notice. I had to go through 'agreed process', phone back the DWP to tell them which email address to send the re-request for decision notice. I also posted DWP copies of both decision notices together with the tribunal email address should they have not acted after the phone call.
Last Monday a lady phoned to say they'd received the notice and that I should receive funds by the end of the week (Fri). I phoned this morning to ask the reason, 'Chloe' told me they'd got the notice but not actioned the payment. Someone would call me back. 3 hours later I call back and 'Candice' rudely tells me I have to wait 3-24 hours for a call-back. I am going to jump. It is now over 5 weeks since the tribunal, I am so stressed, I cannot eat (part of the reason I'm on PIP).
From start to not-even-finished, this saga has been one of the worse times of my life. Due to the 1st examiner lying I have gone 17 months without the support that was actually making me better. I'd started UCAS for entry to a nursing degree, I'd put on 3/4 of a stone, blah blah really.

I'm sorry this is so long, please will someone help me condense the horrid consequences of their ineptitude into some bullet points. I lost 17 months' disability allowance as well as the PIP, so am massively in debt, my health has suffered hugely, now severely underweight, malnourished and almost agoraphobic, lost social life, hobbies and interests. I leave the house only when I have to, my boys (16, 14) are witnessing their strong ox of a mother just disappear.
How can I get the DWP to pay what was decided by the tribunal? I just want to mend.
Thank you for reading, got a lot off my chest.