None of that helps now when you really need it though @Former-Member - the system really is not a good one. 
You have done so well for so long getting through work and looking after your kids - and all that despite still struggling with your mental health. The difference now is that this has been the result of a workplace incident so I can imagine that is not somewhere you can see yourself going back to when you are struggling so much. It is not surprising you feel so trapped.
What I do know of you though Hon is that you do have that inner strength - it may not feel like it right now but pull on your reserves as a good teacher to help you get through just one day at a time - that is all you need to do - approach each day in isolation and just get through. If the worker's comp does come through then you can take some more time off - maybe even use that to have a day off a week for a while whilst you get some more outside help. Are you seeing anyone at the moment?