How will I be able to file for a divorce, if my spouse isn't signing the papers?

You need only have your spouse served and then you can proceed with a default judgment. You should consult a family law attorney or facilitator to assist you with the default procedures.

You file a Complaint for Divorce, and have your spouse served with the papers. The spouse has 20 days to file a response in the court system. If no response is filed, the matter may proceed by default. If a response is filed, the case moves through the system until an agreement is reached or the judge makes a final determination. You would do well to at least consult with an attorney before filing anything in the court system. There are many pitfalls to the "do-it-yourself" process that can result in a multitude of costly and unintended consequences.

You have to file a complaint, hire a process server to try and locate him. If the process serve cannot locate him, he will prepare an Affidavit of Due Diligence. You then file a request with the court to allow you to publish for 4 weeks. At the end of 4 weeks you prepare the appropriate default documents and proceed with your divorce.

Your spouse's signature is not required to file a complaint for divorce, only your signature.

Your spouse doesn't have to sign anything. Just file your papers and have your spouse served with them

You do not need his signature to file the initial papers. After those are file have him personally served. At that point your divorce has begun.

Many, perhaps most actions ending a marriage are not done via an advance agreement. You file a petition for divorce (Dissolution of marriage in Oklahoma) and you have the petition, summons, notice of automatic injunction and, if applicable, application for temporary orders, served on the other party. You can rely on the local sheriff office or use a private process server to serve the papers. Then proceed from there.

In Michigan there is no need for the spouse to sign the complaint.

Surprisingly, your spouse does not need to sign divorce papers or even consent to the divorce. All that is needed in 1 year of separation and 6 months residency of either spouse in order to file. What you file with the court is not the actual divorce decree but a document called a Complaint along with a Summons. You do need to legally serve the lawsuit papers on your spouse (typically certified mail with return receipt via the green card or Sheriff service or the rare situation of legal publication in the newspaper under very complex rules which should only be done with an attorney). If you use certified mail, then technically the other spouse needs to sign something (but only the green card to accept the package, not the actual divorce decree or even the Complaint). The final divorce decree comes at the end once it's time for you to calendar your case, having your hearing, and present your proposed divorce judgment to the judge and it is the judge who signs the actual "divorce papers". If you are doing this on your own, make sure you have one of those Pro se (Do-it-Yourself) divorce packages, which most counties have at the court house and/or online and you can often use one any county so long as you change the county name at the top as well as call the Clerk to verify you have all the proper documents and steps.