First of all

I know how you're feeling I've been there only my kids were older 12 and 10 at the time.
I know exactly what you mean when you say you're tired!
If you want to find out what you're entitled to with Centrelink the best way is to make an appointment and go in to talk to someone there, I know it's a hassle but I got confused with the website too.
Only you can make the final decision as to whether or not you leave but arming yourself with all the info you can about your entitlements is a great idea first.

You did say you think you still love him, is he willing to communicate and work things out? My ex wasn't and in the end I didn't love him anymore, but if you're still in love with him and he's willing there's always a chance to sort things out. Although once you're emotionally exhausted that's hard to think about specially if it feels one sided.

I'm sorry you don't seem to have much support either that, maybe once people know just how bad things are they will kick into support mode? Maybe they just think you're venting at the moment?

I know where you are and how hard it is not knowing what to do, worrying about the kids.
I feel for you I really do hang in there