According to the West Virginia instructions:
A Resident is an individual who spends more than 30 days in the state with the intention of becoming a resident OR is physically present in the state for more than 183 days.
A Nonresident is an individual is a resident of another state that does spend more than 183 days in West Virginia during the year. If you are a resident and spend less than 30 days in West Virginia and maintain a home outside of West Virginia, you are to file as if a nonresident.
A Part-Year Resident is an individual that moves into or out of West Virginia.
If a joint federal return was filed and one spouse is a resident and the other is not, you can file as married filing joint or married filing separate. A married filing joint return will report all income- no matter where earned. A Married filing separate return needs to be filed only by the taxpayer that has a West Virginia filing requirement.
To file a separate return within your account, you can file the federal return and wait for the return to be accepted. Then, change the filing status for the primary taxpayer and file a separate return for the first spouse. The second spouse will need to create a new account and file the separate state return in that account (if required to file).
For more information: