Try it out. You may find other spouses of drug addicts there. Each meeting I have been to is very different, so it's hard to say universally whether you are going to get what you need. It's pretty common for people to be both alcoholics and addicts though, so not unlikely that you can meet some people in your shoes.
I also think there might be a way to find other spouses in your area and create your own group. I'd start by going to some al-anon meetings and asking if they know anyone that would be interested in nar-anon. If you go to church, ask your pastor. Are there NA meetings in your area?
Also, are you sure there are no Nar-Anon meetings around there? How did you check it out? The stuff online is not updated in my area, so I think there are meetings but they are not listed. If I wanted a meeting I'd start by calling the places where NA meetings are held, and asking if there are any resources for friends and family.