Does the destined wife and concubine mean divorce and remarriage?

It means wife and lover. Not divorce and remarriage.

But be careful not to be cheated. The first is superstition. Don't believe such nonsense as fortune telling. Secondly, maybe it's a scam. Your man has a lover outside, and he doesn't want to get a divorce, so he deceives you with a destiny takes a hand story. Don't believe it, it's a fool to believe it.