There are only two grounds for divorce in North Carolina. The first is a one-year separation. You must assert, under oath, that you and your spouse have been living separate and apart for one year.
It is not enough to assert that you have lived in separate bedrooms, or that you have not engaged in acts of sexual intercourse. You must live in separate residences during that year. You do not need to file any papers to document the beginning of your separation; your assertion is sufficient to prove that the year has elapsed.
The second ground for divorce in North Carolina is incurable insanity. However, this is rarely used.