Maybe humans were meant to live alone.
Two facts militate against that hypothesis: the sex drive and its natural consequence, the birth of children. The family seems an inevitable byproduct. Throughout history it has taken many forms, from tribal and clannish to nuclear. But families there have always been.
Does it follow that there always will be? Certain novelties peculiar to our age sow doubts. One is the primacy of individual happiness. Happiness was always desirable, always hoped for, but it was secondary. Obligations deemed sacred, conventions considered "natural," came first. They no longer do.