Each state has its own laws, but generally speaking:
If you and your husband still own and maintain your permanent home to which you intend to return - your domicile in tax lingo - in State A, your income is entirely taxable by State A, regardless of where you earn it. Your husband's military income may or may not be taxable by State A, depending on that state's laws regarding military pay.
State C will tax you as a non-resident (or possibly as a "statutory" resident, depending on how many days you lived there) on your earnings from working within State C. But you may well have to pay taxes to State C as well as State A.
If you never worked in State B, and your husband's only income in State B was his military pay, neither one of you will have a tax obligation to State B.
Your domicile will remain in State A until you establish a new domicile (permanent home) in another state.
We can give you more specifics if you identify States A and C.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
