Firstly Congratulations!!
You cope because you have to hun.
Sleep when you can.
Take help when you can, even if it is a meal, someone to vacuum or someone to change a nappy.
Don't be ashamed to ASK for help.
Get out of the house if you can, playgroups are a great place to meet other mums and not feel so isolated.
I gather your boy starts school this year? That will make things a little easier

I am in Tassie too You've chosen a great place to live!