When a man and a woman exchange wedding vows, it is not a mere dialogue, but a promise to stay together, forever. Around the world, the number of years that couples spend as husband and wife vary -- according to online publication Hopes&Fears, marriage may last at an average of 5.5 years based on trends in Doha Qatar, or as long as 18 years, as evidenced by those living in Italy. Outside these numbers, there is living proof that marriages can stand the test of time, especially if both man and wife are truly committed to a life of togetherness.