Great post @nainaztengra on counselling for couples. One reason why married tend to fail is failure to realised the conviction that when your marrying someone, you are actually marrying 3 things;
- What the person really is
- What you think the person is
- What the person would be as a result of cohabiting with you in Marriage.
Sometimes the things you like before marriage are not real and the quality of the person starts revealing during marriage. Another thing is people change over time due to life events and their interactions with people.
As @nainaztengra said, love is not the main requirement for marriage. You need to each other well, be ready for commitment, tolerance, patience, understanding, trust and communication.