I believe that it's up to the individuals involved....my grandparents were married when they were 18 and 19. They were married for 68 years til grandpa passed on this year. My parents were married at the ages of 19 and 21 and have been married for 42 years. I got married late in life because I hadn't found anyone I wanted to marry til I met my husband. We have been together for nine years and married for 5.