This book was written by a man who had two successful marriages (both his wives passed). Well worth reading.
Here is a quote from the book.
It may be that you have sincerely sought God concerning marriage, and He has not given you a definite answer one way or the other. He has not given you a mate, but He has not shown you that it is His will for you to remain single. If so, you need to follow the advice of David in Psalm 37:7–8: “Be still before the Lord and wait patiently for him. . . . Do not fret—it leads only to evil.” Give yourself wholeheartedly to serving God in your present condition, and leave the future in His hands. Your attitude of quiet trust will keep you open to any direction the Lord may intend to give you farther down the road.