I really feel for you right now :-(

Can you contact a local family daycare scheme and see if you can book your little one in for a few days, you should be able to get some help from centrelink in regards to fees and during that time you can make time for yourself... otherwise is there a friend you could perhaps ask to watch her? maybe someone close could have Miss S for a night just to allow you to get a full night sleep to get back on top...

Wish I could help more