If your wife does not agree with the terms of the dissolution of marriage that you proposed, she does not have to sign the documents.
If you want to proceed, you will need to go through the legal procedures. If you two cannot resolve your issues, eventually the court will hold a trial and decides the issues for you.
The exact steps are more complicated, especially if you two disagree.
You can review some information provided by WA LegalHelp at http://www.washingtonlawhelp.org/WA/index.cfm . The law library at the county's superior courthouse also has many books. From various sources, you likely can figure out what needs to be done.
Often, it is much more cost effective to hire an attorney to take care of things.
To file for divorce, you do not need your wife's signature. If you can come to an agreement at a later time, you can speed up the process. (It will take a minimum of 90 days in WA)
You will need to file the documents with the court and will need to ensure that your wife is served with the papers. If she will not sign for receipt of the filed petition and summons, you can have her served by a non-party over 18 years of age.
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