@neverending,
I think your wife is telling you that she is depressed. Her behavior is consistent with a depression.
Can you get her to talk about any of the things that are bothering her? Do you have any clues about what it might be?
First off, you need to improve communication between you and your wife. She has to be able to tell you what is bothering her, whether it is something in the marriage, or something you are doing, or not doing, or something that only relates to her. You have to try to encourage her to talk, and just listen patiently when she does. As long as she remains withdrawn, you won't be able to help her, or support her, or to address any of the things that might be bothering her. Let her know that, in an understanding way.
Also, tell her you are very concerned about her and the fact that she seems to be depressed and unhappy. Tell her you want to make an appointment for you both to meet with a doctor, preferably a psychiatrist, if one is available where you are stationed. If she is depressed, it really is a problem for both of you, so there is good reason for you both to see a doctor together and describe the situation to that person. That person might be able to get your wife to open up a little more about what is bothering her. He/she might also be able to assess whether your wife might benefit from some medication for depression. But, it is important that your wife begins talking about her problems first. Medication might be unnecessary if her problems can be addressed by talking about them. A chaplain might be helpful, regarding some marriage counseling with both of you, but I think that you would be better off speaking to a doctor first--both of you. Your wife can always decide to continue speaking with someone on her own if that would be more helpful for her. Depression is a problem which should not be ignored.