You really need an attorney to help you sort this out. It is unclear what type of hearings you missed, what rulings have been made, and when this all occurred (there are deadlines for different types of relief that may or may not have passed). If you are a King County resident, your case doesn't need to be here to qualify for assistance here--the King County Bar Association has a lot of great programs available: http://www.kcba.org/pbs/legalhelp.aspx
You can also try the statewide referral resource line: http://nwjustice.org/get-legal-help
If the TMI was sustained in military service, talk to JAG and ask for a referral to the ABA Military Pro Bono Project.
Regarding the additional information in your post, Washington is a no-fault state--infidelity is irrelevant, the courts are specifically prohibited from considering misconduct in a dissolution case. You need to focus on getting involved in your case to fix what has happened so far and make sure you have the opportunity to be heard from now on--an attorney can help you understand what information a court will be willing to consider.
Make sure you show up at any scheduled hearing or trial. Explain this situation to the Judge. If you can demostrate inability to defend yourself due to your brain injury, the court should vacate the prior order, and appoint a Guardian Ad Litem for you to help present your case. See my AVVO Legal Guides for a possible explanation of the legal issues raised by your question. To find my Legal Guides, go to my AVVO home page by clicking on my photo; scroll down to "Contributions" and then click "Legal Guides." You will get a list of the 29 Legal Guides I have published on AVVO. Scroll down this list and select the topics that are relevant to your question.
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