Getting divorced from your spouse if he or she lives in a different state than Texas is possible. If you have resided in Texas for at least the past 180 days and in Montgomery County (or any other Texas county) for the past 3 months, then you may file for divorce in Texas. It will not matter if your spouse has resided in Texas during that same time. Bear in mind that if your spouse has resided in another state for an extended period then he or she will likely be able to qualify for residency in that state and can file for divorce from you in another state.
If your spouse and you have been physically separated from one another for an extended period, then you may be facing circumstances where he or she could file for divorce in a new state. This means you could end up having to travel to a new state just to get divorced! To avoid a situation like this, you may want to file for divorce in Montgomery County before your spouse files for divorce in another county in Texas or even in another state. By you filing first in Texas, another court would likely cede jurisdiction of the divorce to a Montgomery County family court.
At a bare minimum your assets, debts, and current bank account balances (checking and savings accounts) will need to be disclosed because of your divorce. An inventory and appraisement are also required in Montgomery County. An inventory and appraisement are a form where you will detail all of the property you own along with an estimate of the value (in dollars) for each items. Depending on whether your spouse issues discovery requests for you to respond to the financial disclosures you need to make in your case may be more significant than this.
If you cannot locate your spouse, it is possible to obtain a default judgment against him or her. This would allow you to get a divorce legally despite their not having participated in the case. To get a default judgment, you would have needed to have attempted to serve him or her personally, locate their whereabouts and then document your efforts for the court. Once the court is satisfied that you have exhausted all available resources to locate your spouse and notify him or her of the divorce then a default judgment will be granted.
In Montgomery County, like all Texas counties, property obtained during your marriage is classified as community property and will be subject to division in your divorce. Being able to distinguish between community property and the property that belongs in the separate estates of you and your spouse will be an important process in your divorce. A just and right division of the property would occur in a divorce trial, but you and your spouse are able to divide the property between yourselves in mediation however you see fit (within reason).