Wow, same story with my inlaws. Although, they did remarry other people in the end. No annulment until my FIL was practically on his deathbed and thought he could fool God by rushing an annulment but secretly stayed with his last wife. Told her it was so the Catholic Church could get him into heaven. What a fool he was.
My Grandfather did remarry years after their second divorce.
Anyway, forgive me if I scoff at the church and its policies around divorce.
Treating divorce as though it is an unforgivable sin is to deny the very grace of God and failing of man.