Just wanted to say, Hitch, that Bill is making great good sense here, as are divine & others.

This can get pretty bumpy, but: He DOES have to pay support for the kiddos, and likely good-sized maintenance for you as well. In the state where I got divorced, they have "Required Divorce Mediation" in place; I went w/my lawyer & he arrived w/his; 30 min later everyone withdrew fuming, lol -- but our experience was NOT typical! IDK what the set-up is in OZ, but yes, please dear, get thee a lawyer! Many folks have gotten thru a divorce & paid lawyer afterwards from proceeds of property sale or other arrangements.
I know you're in some respects utterly terrified, dear: but this too shall pass, and arming yourself w/legal representation is the only way to keep from getting Pearl-Harbored a second time.
xo, chin up !
Chyia, knowing you can do this!