How come so many natives are single in japan male and female?

Question:

for both male and female,
i don't understand the otaku crave (or the yaoi crave) when there's so many gorgeous woman fluttering about; and equally so for handsome men; (that seriously discredit themselves)
is it that hard to say hello and go from there?

Answer:

Why do we need to get married?
The only reason I can think of is to have children and make "a family."
But I can sense that more and more people in Japan are losing a desire to have children.
Probably because, 1) Japan is overpopulated; 2) raising a child costs a large (if not enormous) amount of money.

In fact, the population of Japan is decreasing. Although the government is encouraging the nation to "produce" more children "in order to" maintain our social security system, a large portion (if not majority) of the nation knows (consciously or unconsciously) that Japan needs to reduce its population extensively to attain 1) more comfortable living environment, 2) higher standard of living and 3) less competitive society in this small country with virtually no natural resources.

I guess this "mass psychology" is working behind the scene of our society, which discourages the nation to get married in their most "productive" period of life. It goes without saying that less and less people want to get married.