http://lawyers.findlaw.com/lawyer/firm/Divorce/Houston/Texas is a directory of divorce lawyers in or near Houston, some of whom offer a free consultation. You can have an attorney file the divorce papers even if you are not in the US.
If your spouse ever lived in Sweden you may be able to file for divorce there.
The first condition in order to be able to file a petition for divorce to a Swedish court is that the Swedish court must actually have jurisdiction to hear the case. That is of course the case where both spouses are Swedish nationals and live in Sweden. But Swedish courts also have jurisdiction in the following cases:
· where both spouses are Swedish nationals,
· where the petitioner is a Swedish national and is habitually resident in Sweden or has previously been habitually resident in Sweden since he or she reached the age of 18,
· where the petitioner is not a Swedish national, but has been habitually resident in Sweden for at least one year,
If you have lived there over a year, you can file for a divorce in Sweden.
http://www.hg.org/law-firms/Family-Law/Sweden/Stockholm.html lists one law firm in Stockholm that handles divorce cases.
If possible, I woulf file in Sweden.