WA family law, divorce decree, child support, no agreement for final court order

Going before the Judge for signing the divorce papers - no agreement - so now what happens?: Every time my husband and I get together to hammer out the decree and child support order we have no problems. We come to an agreement that we can both live with. Then he goes back to his apartment and girlfriend and the next time we talk, he wants changes. These changes always leave me holding the short end of the stick. So far, just to get out of the marriage - I've agreed to everything. He'd been making plans for the last year. I got blind-sided by all this. Whenever there is an argument, I just seem to lose my ability to think or speak. It's like 5 minutes later you think I should have said "this" or "that". Our court date is in two weeks and neither of us have a lawyer or have used one except for mediation and collaboration. Can I hire a lawyer as an advocate to speak for me in court for the decree and child support order so I don't get all tongue-tied? Question is do I need to inform him ahead of time that I plan to do this? Can I simply not sign his version of the decree and child support order, but sign a version of my own for my lawyer or myself to file or present? Do I have to be there since he is the petitioner? Can my lawyer go in my stead? Will the judge make a decision between the two versions or throw us out and tell us to come back when we are in agreement? Thanks for your time.