More times than you would think, people get married and then split up without getting a divorce.  After that, they would like to divorce their spouse, but have lost touch with them and have no way to contact them.  It is still possible to achieve a divorce, it just requires a few extra steps.  First, a normal complaint for divorce is filed.  Thereafter, a motion for substituted service is filed.  In that motion, you request to serve them by publication (newspaper) or by some other means allowed by the judge.  In one of my cases, a judge allowed my client to serve his missing spouse by way of Facebook.

When you file your motion for substituted service, you must submit a certification stating when the last time you saw your spouse was and why you do not know where they are and, most importantly, what you have done to find them.  The judge will want to know if you have any contact with their friends or relatives, have their phone number or email address, did a United States Postal search, and did a motor vehicle search for them.  With social media websites like Facebook, it makes sense to search for them on there as well.  The process for divorce will be easier if you do find your spouse.  If you do not, and you have shown that you have exhausted all of your remedies to find them, it is likely the judge will grant your motion for substituted service. 

After your complaint was served in the manner allowed by the Court, your spouse will still have the same 35 days to respond as if they were personally served.  If they fail to file an answer or appearance within this time period, a default may be entered against them.  After the default is entered, a default hearing will be scheduled, which you also must notice your spouse in the same alternate manner that you originally served them.  Then, at the default hearing, if you prove your cause of action, you can achieve your divorce.