Is a married human being happier than unmarried one?
Only for legal reasons. albatross stay with each other for a really long life and don't need someone they pay to tell them they can be together.
You can be alone and unhappy or alone and happy. You can be married and unhappy or you can be married and happy. If you marry someone who turns out to be unhappy most of the time you have a choice as to whether or not to remain in that marriage.
I do not think that anyone can make another person person happy but he or she sure can make another person unhappy.
Check the post of the married without intimacy for 6 years and get back to us.