Why were women really needed in Shakespeare's plays?

If plays are a reflection of life and the people who live
life, then women are essential.  Shakespeare was a great observer of the human
condition.  Women are a part of that.

In his comedies, the
women are important because he is able to show us strong, intelligent, and independent
women.  Most of the male characters don't truly understand what love is until they meet
one of these women (often disguised as males).

Many of
Shakespeare's plays deal with love and how can you have a Romeo without a Juliet?  Where
would the great love of Antony be without Cleopatra?

Where
would the play King Lear be without his daughters.  Father and son relationships are
quite different from father daughter relationships.  Shakespeare had two
daughters.

I could go on but the answer should be obvious. 
Women make up more than half of the population.  They are lovers, wives, mothers,
daughters, sisters, etc.  Shakespeare gave us all of these.