I dont know all about your situation but I will tell you about mine.
My husband has two young children to his ex partner. When she left him, she moved 9 hours away. It was hard for my husband to have contact due to work etc so he became angry. He could not understand how everything works for the mother. For example, the mother has automatic custody, the mother makes the decisions etc. My husband could not follow her due to work etc. It has been over 4 years and we are still fighting for fair contact through the courts.
Did you live in Sydney with your husband before the split? If so, have you thought about moving back?
I think you need to evaluate what is best for your child. I know that break ups are hard and you need your family around but your child needs Dad. If you husband doesn't seem to be making an effort and you want your child to see their father, you can lodge an application in Family Court for him to have contact.
I dont know if this has helped but as the wife of a father who doesn't see his children, I ask that you try and understand how the father feels having lost not only his wife but also his child.
Mum to Samuel - 3 and Jordy - 22 months